leptin has been researched along with Myocardial-Infarction* in 60 studies
1 review(s) available for leptin and Myocardial-Infarction
Article | Year |
---|---|
[Leptin--a new acute phase reactant].
Leptin, 16 kDa protein and the product of the Ob gene was discovered six years ago and characterized as a fat cell hormone which maintains via specific receptors in the hypothalamus by a feedback mechanism the energy balance and body weight. Research conducted during the last three years detected further properties of this protein which include it, in addition to its basic role in mammalian metabolism, also among acute phase reactants. Leptin is as to its structure, pattern of the receptor and the postreceptor transduction mechanism close to the group of cytokines of interleukin 6, in particular the granulocytic colony stimulating factor. During infectious and non-infectious inflammatory reactions leptin synthesis is stimulated by a combination of inflammation promoting cytokines. The mechanism of induction is not known so far but the majority of investigations proves an indirect stimulating effect of the tumour necrosis factor and interleukin 1, depending on non-specified cytokines of the second stage. Investigations of cell lines and animal experiments provided evidence of some local and systemic effects of leptin which may play a physiological part in the acute phase reaction. Leptin mediates at least partly the anorectic effect of the tumour necrosis factor and interleukin 1 during inflammation. Synergically with bacterial antigens it activates macrophages, enhances their phagocytic capacity and stimulates secretion of pro- and anti-inflammatory factors from macrophages. Leptin stimulates neovascularization, it has a stimulating effect on precursors of white blood cells and potentiates the effect of erythropoietin on red blood cells. It is obviously an essential factor for T-lymphocyte proliferation and development. The authors discuss also the role of leptin in the modulation of the hypothalamo-pituito-adrenal stress axis. Leptin is a factor of the inflammatory mediator network, probably essential for an adequate course of the inflammatory defence reaction. Topics: Acute-Phase Proteins; Acute-Phase Reaction; Animals; Cytokines; Humans; Leptin; Myocardial Infarction; Sepsis | 2001 |
8 trial(s) available for leptin and Myocardial-Infarction
Article | Year |
---|---|
Insulin Resistance Modifies the Effects of Omega-3 Acid Ethyl Esters on Left Ventricular Remodeling After Acute Myocardial Infarction (from the OMEGA-REMODEL Randomized Clinical Trial).
Insulin resistance early after acute myocardial infarction is associated with increased heart failure and mortality. OMEGA-REMODEL was a prospective double-blind 1:1 randomized control trial of patients with AMI. We reported that 6-month treatment with omega-3 fatty acid (O-3FA) 4 g/day attenuated cardiac remodeling accompanied by reduction in inflammation. We hypothesized that insulin resistance modifies the therapeutic effect of O-3FA on post-MI cardiac remodeling. The OMEGA-REMODEL study group was dichotomized according to cohort- and gender-specific median cutoff value of leptin-to-adiponectin ratio (LAR) at baseline (LAR-Hi vs LAR-Lo). Mixed model regression analyses were used to evaluate effect modification of O-3FA on reduction of left ventricular end-systolic volume index (LVESVI) by LAR status. Baseline LAR was evaluated on 325 patients (59 ± 11 years, 81% male). A total of 168 patients were categorized in LAR-Lo, and 157 in LAR-Hi. O-3FA treatment resulted in significant LVESVI reduction in patients with LAR-Lo but not with LAR-Hi (p = 0.0002 vs 0.66, respectively). Mixed model regression analysis showed significant modification of LAR on O-3FA's treatment effect in attenuating LVESVI (p = 0.021). In conclusion, this post-hoc efficacy analysis suggests that LAR status significantly modified O-3FA's treatment effect in attenuating cardiac remodeling. During the convalescent phase of acute infarct healing, patients with lower insulin resistance estimated by LAR appear to derive more therapeutic response from O-3FA toward improvement of LVESVI. Topics: Adiponectin; Aged; C-Peptide; Double-Blind Method; Fatty Acids, Omega-3; Female; Humans; Insulin Resistance; Leptin; Male; Middle Aged; Myocardial Infarction; Prognosis; Proinsulin; Stroke Volume; Treatment Outcome; Ventricular Remodeling | 2020 |
Leptin levels are not affected by enalapril treatment after an uncomplicated myocardial infarction, but associate strongly with changes in fibrinolytic variables in men.
Leptin, an adipocyte-derived hormone, is involved in the regulation of body weight and is associated with obesity-related complications, notably cardiovascular disease (CVD). A putative link between obesity and CVD could be induction of plasminogen activator inhibitor-1 (PAI-1) synthesis by leptin. In this study, we hypothesized that the beneficial effect of the angiotensin-converting enzyme inhibitor (ACE Topics: Aged; Angiotensin-Converting Enzyme Inhibitors; Antihypertensive Agents; Double-Blind Method; Enalapril; Female; Fibrinolysis; Gene Expression Regulation; Humans; Leptin; Male; Middle Aged; Myocardial Infarction; Obesity; Plasminogen Activator Inhibitor 1; Protein Binding; Sex Factors; Signal Transduction; Tissue Plasminogen Activator | 2020 |
Hesperidin supplementation modulates inflammatory responses following myocardial infarction.
A growing number of studies have suggested a crucial role for a variety of inflammatory mediators in myocardial infarction. Recently, several flavonoids have been shown to have cardioprotective and anti-inflammatory properties. Therefore, the aim of this study was to investigate the effect of hesperidin-a common constituent of citrus fruits-on the serum levels of inflammatory markers and adipocytocines in patients with myocardial infarction.. Seventy-five patients with myocardial infarction were participated in this randomized, double-blind controlled clinical trial and were assigned to 2 intervention and control groups. Subjects consumed 600 mg/d pure hesperidin supplement and placebo in the intervention and control groups, respectively, for 4 weeks. Serum concentrations of inflammatory markers and adipocytocines were measured at baseline and at the end of the intervention.. Consumption of 600 mg/day hesperidin significantly decreased the serum levels of E-selectin and increased adiponectin and high-density lipoprotein cholesterol (HDL-C) concentrations in patients with myocardial infarction. The improvement in other inflammatory markers, such as interleukin (IL)-6, high-sensitivity C-reactive protein (hs-CRP), leptin, and other lipid profile was also observed at the end of the intervention, compared to the baseline values, but the difference between the hesperidin and placebo groups was not statistically significant (p > 0.05).. Hesperidin supplementation could compensate for decreased levels of adiponectin and HDL-C and increased levels of E-selectin in patients with myocardial infarction. These results support the concept that certain flavonoids in the diet can be associated with significant health benefits, including heart health. Topics: Adipokines; Adiponectin; Adult; Biomarkers; C-Reactive Protein; Cholesterol, HDL; Dietary Supplements; Double-Blind Method; E-Selectin; Female; Hesperidin; Humans; Inflammation; Interleukin-6; Leptin; Male; Middle Aged; Myocardial Infarction; Placebos | 2015 |
On-Statin Resistin, Leptin, and Risk of Recurrent Coronary Events After Hospitalization for an Acute Coronary Syndrome (from the Pravastatin or Atorvastatin Evaluation and Infection Therapy-Thrombolysis in Myocardial Infarction 22 Study).
Resistin is an adipokine secreted by macrophages and inflammatory cells linked to insulin resistance and inflammation. Leptin is an adipokine regulator of appetite and obesity. Although circulating levels of both have been associated with atherosclerosis, few data have reported their relation to coronary events in the context of statin therapy. This study measured on-statin levels of both resistin and leptin through enzyme-linked immunosorbent assay in a nested case-control cohort (n = 176 cases with coronary death, myocardial infarction, or unstable angina pectoris observed in follow-up matched 1:1 to 176 controls) derived from the Pravastatin or Atorvastatin Evaluation and Infection Therapy-Thrombolysis in Myocardial Infarction 22 study, a randomized controlled trial of atorvastatin 80 mg/day versus pravastatin 40 mg/day in patients with a recent acute coronary syndrome. Resistin demonstrated a moderate association with high-sensitivity C-reactive protein (hsCRP; Spearman rho = 0.25, p <0.0001). On-statin resistin levels were linked to recurrent coronary events in conditional logistic regression analysis adjusted for additional risk factors including hsCRP and history of diabetes (tertile 3 vs 1 adjusted odds ratio 2.08; 95% confidence interval [CI] 1.04 to 4.19). An additive risk was noted when patients were stratified by resistin and glycated hemoglobin levels. In contrast, leptin levels were associated with obesity, diabetes, triglycerides, and hsCRP (p <0.001 for each) but demonstrated no association with recurrent coronary events (tertile 3 vs 1 adjusted odds ratio 0.72; 95% CI 0.28 to 1.83). In conclusion, on-statin resistin, but not leptin, is an independent marker of residual risk for recurrent coronary events in patients after hospitalization for an acute coronary syndrome. Topics: Acute Coronary Syndrome; Aged; Atorvastatin; Biomarkers; Dose-Response Relationship, Drug; Double-Blind Method; Enzyme-Linked Immunosorbent Assay; Female; Follow-Up Studies; Heptanoic Acids; Hospitalization; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Infections; Leptin; Male; Middle Aged; Myocardial Infarction; Odds Ratio; Pravastatin; Pyrroles; Recurrence; Resistin; Retrospective Studies; Risk Factors; Survival Rate; Thrombolytic Therapy; United States | 2015 |
Functional polymorphisms of the leptin and leptin receptor genes are associated with longevity and with the risk of myocardial infarction and of type 2 diabetes mellitus.
Longevity is commonly associated with good health and with delayed onset of age-related diseases with usually benign course. Leptin (LEP) significantly affects metabolism and numerous functions of the organism. To find out if extreme longevity and its phenotype are associated with genetic variants of leptin and leptin receptor (LEPR) genes, we analysed the frequencies of the -2548 G/A and +19 G/A LEP, as well as the K109R, Q223R, and K656N LEPR polymorphisms in centenarians and in control groups.. The frequencies of the LEP and LEPR polymorphisms were tested by restriction fragment length polymorphism in 128 centenarians, 414 young controls (Y), 226 myocardial infarction (MI) patients, and 190 type 2 diabetes mellitus (DM2) patients.. The GG genotype of the -2548 G/A LEP polymorphism was significantly more common in centenarians than in the Y, MI and DM2 groups (p = 0.048, p = 0.003, p = 0.049, respectively). In addition, the AA genotype of the K109R LEPR polymorphism was significantly less frequent in centenarians than in the Y, MI, and DM2 groups (p = 0.026, p = 0.013, and p = 0.001, respectively).. We suggest that the leptin pathway plays a role in the regulation of longevity, possibly by modulating the risk of development of MI and of DM2. Topics: Adolescent; Adult; Aged; Aged, 80 and over; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genetic Predisposition to Disease; Genotype; Humans; Leptin; Longevity; Male; Middle Aged; Myocardial Infarction; Polymorphism, Genetic; Receptors, Leptin; Young Adult | 2014 |
Impact of adiponectin and leptin on long-term adverse events in Japanese patients with acute myocardial infarction. Results from the Nagoya Acute Myocardial Infarction Study (NAMIS).
Low adiponectin levels and high leptin levels are associated with a high incidence of developing cardiovascular disease. However, the relationship between the levels of these adipokines and the development of adverse events after acute myocardial infarction (AMI) remains unclear.. This study enrolled 724 Japanese subjects with AMI who underwent successful emergency percutaneous coronary intervention (PCI). Their serum adiponectin and leptin levels were measured 7 days after AMI onset. There were 63 adverse events during the 3-year follow-up. The levels of adiponectin and leptin and the leptin to adiponectin ratio, were significantly associated with adverse events [hazard ratio 2.08 (95% confidence interval (CI) 1.33-3.24), P=0.001; hazard ratio 0.62 (95% CI 0.43-0.90), P=0.012; hazard ratio 0.59 (95% CI 0.45-0.76), P<0.001, respectively]. The leptin to adiponectin ratio remained a significant independent predictor of adverse events during long-term follow-up in a multivariable analysis [adjusted hazard ratio 0.60 (95% CI 0.43-0.83), P=0.002].. Higher adiponectin and lower leptin levels are associated with a high incidence of adverse events in Japanese patients after AMI, and the leptin to adiponectin ratio independently predicts prognosis after AMI. Topics: Adiponectin; Aged; Asian People; Female; Humans; Incidence; Japan; Leptin; Male; Middle Aged; Myocardial Infarction; Percutaneous Coronary Intervention; Prognosis; Time Factors | 2013 |
The predictive value of inflammatory activity and markers of the adipo-insular axis on restenosis in patients with type 2 diabetes.
Patients with type 2 diabetes (T2DM) have a high restenosis rate after percutaneous coronary intervention (PCI). This study investigated whether markers of inflammation and the adipo-insular axis associated with T2DM and poor metabolic control were able to predict restenosis after PCI in T2DM patients.. The predictive value of traditional and non-traditional risk markers, including IL-1β, IL-6, TNF-α, hsCRP, interferon gamma, leptin, IGF-I, insulin, proinsulin and NT-proBNP, was investigated in 82 patients with T2DM. A re-angiography 6 months after the index percutaneous coronary intervention (PCI) revealed that 43% of the patients had a restenosis. In a multiple regression analysis, the only independent predictors of restenosis were fasting glucose before the PCI and previous myocardial infarction (odds ratio [OR] 1.44, 95% confidence interval [CI] 1.07-1.92; p = 0.015 and OR 8.00, 95% CI 2.49-25.67; p ≤ 0.001, respectively). None of the other markers remained as significant predictors.. Fasting glucose prior to the PCI was an independent predictor of restenosis in patients with T2DM while analyses of a variety of markers related to inflammation and the adipo-insular axis did not add any further information. Topics: Aged; Angioplasty, Balloon, Coronary; Biomarkers; Blood Glucose; Coronary Angiography; Coronary Restenosis; Coronary Stenosis; Cytokines; Diabetes Mellitus, Type 2; Female; Humans; Hypoglycemic Agents; Inflammation Mediators; Insulin; Insulin-Like Growth Factor I; Leptin; Logistic Models; Male; Middle Aged; Myocardial Infarction; Natriuretic Peptide, Brain; Odds Ratio; Peptide Fragments; Proinsulin; Prospective Studies; Risk Assessment; Risk Factors; Sweden; Time Factors; Treatment Outcome | 2011 |
Leptin, but not adiponectin, is a predictor of recurrent cardiovascular events in men: results from the LIPID study.
To investigate the relationships between plasma leptin and adiponectin levels and recurrent cardiovascular events (cardiovascular death, nonfatal myocardial infarction and stroke) in men with earlier acute coronary syndromes.. A nested case-control study examined circulating leptin and adiponectin levels in plasma obtained 4-6 years after entry into the Long-Term Intervention with Pravastatin in Ischaemic Disease (LIPID) trial. Plasma was assayed from 184 men who suffered recurrent events within 4.4 years after blood collection and 184 matched controls who remained free of further events. The association between cardiovascular events and the explanatory variables was examined by conditional logistic regression analysis.. Relative risk (RR) increased across increasing leptin quartiles; the highest quartile compared with the lowest quartile was related to the highest risk (P for trend=0.002); the increased risk remained after adjustment for risk factors (P=0.018) or for obesity (P=0.038), but in the final model (adjusted for randomized treatment, other drugs, LIPID risk score, age and body mass index), the risk was attenuated (RR=1.61, 95% CI: 0.72-3.57, P for trend=0.34). Adiponectin did not predict cardiovascular events. Subjects randomly allocated to pravastatin had 6% lower leptin levels (P=0.04) than those allocated to placebo.. Plasma leptin was a significant and independent predictor of recurrent cardiovascular events (cardiovascular death, nonfatal myocardial infarction and stroke) in men with earlier acute coronary syndromes. Topics: Adiponectin; Aged; Biomarkers; Cardiovascular Diseases; Case-Control Studies; Coronary Disease; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Leptin; Logistic Models; Longitudinal Studies; Male; Middle Aged; Myocardial Infarction; Natriuretic Peptide, Brain; Peptide Fragments; Pravastatin; Recurrence; Risk; Stroke | 2009 |
51 other study(ies) available for leptin and Myocardial-Infarction
Article | Year |
---|---|
Association of serum leptin and resistin levels among obese Saudi patients with acute myocardial infarction in Asir region.
In the current scenario, the importance of cardiac biomarkers in diagnosing, assessing, and managing people with cardiovascular discomfort is required. This cross-sectional study examined the relationship between serum leptin and resistin levels among obese people with acute myocardial infarction (AMI) with varying body mass index (BMI). The cardio and diabetic biomarkers among the 77 Saudi patients with hypoxia who lived in the Asir region were analyzed in the study. The patients were categorized into three groups, namely, group 1 (control), group 2 (AMI with normal BMI), and group 3 (AMI with varying BMI). Our results showed a positive correlation between serum glucose, HbA1C, triglycerides, Troponin-I (cTnI), creatine kinase MB (CK-MB), leptin, and resistin in patients with AMI. We also observed significantly lower HbA1C, cholesterol, and insulin values in groups 2 and 3. A statistical difference between the groups with and without AMI and between the genders was noticed. BMI with leptin showed a positive connection in group 3 but no association was observed for groups 1 and 2. A stronger relationship between BMI and leptin levels in men in Group 3 than in women was observed. In all three groups, resistin levels did not correlate with BMI. Thus, circulating leptin concentrations do not significant impact AMI compared to participants with and without AMI. However, resistin levels were considerably higher in obese individuals with AMI. Therefore, we suggest that resistin can be used as a pro-inflammatory marker to detect AMI disorder with varying BMI and as a prognostic marker associated with AMI. Topics: Cross-Sectional Studies; Female; Glycated Hemoglobin; Humans; Leptin; Male; Myocardial Infarction; Obesity; Resistin; Saudi Arabia | 2023 |
Leptin as predictor of cardiovascular events and high platelet reactivity in patients undergoing percutaneous coronary intervention.
Leptin is a hormone involved in the regulation of food intake. Previous studies suggested an interplay between leptin, platelet aggregation, and cardiovascular outcome but this issue was not investigated in vivo in patients treated with percutaneous coronary intervention (PCI). We designed a study to evaluate the possible relation between leptin, cardiovascular outcome, and platelet reactivity (PR) in patients undergoing PCI.. 155 PCI patients had preprocedural measurements of PR and leptin plasma levels. The latter were assessed by ELISA. Hyperleptinemia was defined as leptin levels ≥14 ng/ml. PR was evaluated by the VerifyNowP2Y12 assay and expressed as P2Y12 reaction units (PRU). Patients were divided into three groups based on PR values and defined as low (LPR), normal (NPR), and high (HPR). Patients were followed for up 8 years. The primary endpoint was the incidence of Major Acute Cardiac Events (MACE) at long-term follow-up according to leptin groups. Secondary endpoints were the evaluation of leptin levels according to PR groups and the incidence of periprocedural myocardial infarction (PMI) according to leptin groups.. Long-term follow-up was completed in 140 patients. Patients with hyperleptinemia experienced a higher MACE rate than the normoleptinemic group (HR 2.3; CI 95% 1.14-4.6, P = 0.02). These results remained unchanged after adjusting for Body Mass Index, hypertension, and gender. Leptin levels were significantly different among groups of PR (P = 0.047). Leptin levels were higher in the HPR group (12.61 ± 16.58 ng/ml) compared to the LPR group (7.83 ± 8.87 ng/ml, P = 0.044) and NPR group (7.04 ± 7.03 ng/ml, P = 0.01). The rate of PMI was higher in hyperleptinemia patients (15.1% vs. 6.5%, P = 0.22).. This study suggests that high leptin levels are associated with a worse clinical outcome in patients undergoing PCI and with HPR. Further studies are needed to define better the pathophysiological pathways underlying this association. Topics: Humans; Leptin; Myocardial Infarction; Percutaneous Coronary Intervention; Platelet Aggregation Inhibitors; Treatment Outcome | 2023 |
High leptin status indicates an increased risk of mortality and heart failure in stable coronary artery disease.
Leptin is an adipocyte-derived peptide involved in energy homeostasis and body weight regulation. The position of leptin in cardiovascular pathophysiology remains controversial. Some studies suggest a detrimental effect of hyperleptinemia on the cardiovascular (CV) system, while others assume the role of leptin as a neutral or even protective factor. We have explored whether high leptin affects the mortality and morbidity risk in patients with stable coronary heart disease.. We followed 975 patients ≥6 months after myocardial infarction or coronary revascularization in a prospective study. All-cause or cardiovascular death, non-fatal cardiovascular events (recurrent myocardial infarction, stroke, or any revascularization), and hospitalizations for heart failure (HF) we used as outcomes. High serum leptin concentrations (≥18.9 ng/mL, i.e., 4th quartile) were associated with worse survival, as well as with a higher incidence of fatal vascular events or hospitalizations for HF. Even after full adjustment for potential covariates, high leptin remained to be associated with a significantly increased 5-years risk of all-cause death [Hazard risk ratio (HRR) 2.10 (95%CIs:1.29-3.42), p < 0.003], CV death [HRR 2.65 (95%CIs:1.48-4.74), p < 0.001], and HF hospitalization [HRR 1.95 (95% CIs:1.11-3.44), p < 0.020]. In contrast, the incidence risk of non-fatal CV events was only marginally and non-significantly influenced [HRR 1.27 (95%CIs:0.76-2.13), p = 0.359].. High leptin concentration entails an increased risk of mortality, apparently driven by fatal CV events and future worsening of HF, on top of conventional CV risk factors and the baseline status of left ventricular function. Topics: Coronary Artery Disease; Heart Failure; Humans; Leptin; Myocardial Infarction; Prospective Studies; Risk Factors | 2022 |
Pericoronary fat inflammation and Major Adverse Cardiac Events (MACE) in prediabetic patients with acute myocardial infarction: effects of metformin.
Pericoronary adipose tissue inflammation might lead to the development and destabilization of coronary plaques in prediabetic patients. Here, we evaluated inflammation and leptin to adiponectin ratio in pericoronary fat from patients subjected to coronary artery bypass grafting (CABG) for acute myocardial infarction (AMI). Furthermore, we compared the 12-month prognosis of prediabetic patients compared to normoglycemic patients (NG). Finally, the effect of metformin therapy on pericoronary fat inflammation and 12-months prognosis in AMI-prediabetic patients was also evaluated.. An observational prospective study was conducted on patients with first AMI referred for CABG. Participants were divided in prediabetic and NG-patients. Prediabetic patients were divided in two groups; never-metformin-users and current-metformin-users receiving metformin therapy for almost 6 months before CABG. During the by-pass procedure on epicardial coronary portion, the pericoronary fat was removed from the surrounding stenosis area. The primary endpoints were the assessments of Major-Adverse-Cardiac-Events (MACE) at 12-month follow-up. Moreover, inflammatory tone was evaluated by measuring pericoronary fat levels of tumor necrosis factor-α (TNF-α), sirtuin 6 (SIRT6), and leptin to adiponectin ratio. Finally, inflammatory tone was correlated to the MACE during the 12-months follow-up.. The MACE was 9.1% in all prediabetic patients and 3% in NG-patients. In prediabetic patients, current-metformin-users presented a significantly lower rate of MACE compared to prediabetic patients never-metformin-users. In addition, prediabetic patients showed higher inflammatory tone and leptin to adiponectin ratio in pericoronary fat compared to NG-patients (P < 0.001). Prediabetic never-metformin-users showed higher inflammatory tone and leptin to adiponectin ratio in pericoronary fat compared to current-metformin-users (P < 0.001). Remarkably, inflammatory tone and leptin to adiponectin ratio was significantly related to the MACE during the 12-months follow-up.. Prediabetes increase inflammatory burden in pericoronary adipose tissue. Metformin by reducing inflammatory tone and leptin to adiponectin ratio in pericoronary fat may improve prognosis in prediabetic patients with AMI. Trial registration Clinical Trial NCT03360981, Retrospectively Registered 7 January 2018. Topics: Adiponectin; Adipose Tissue; Aged; Biomarkers; Coronary Artery Bypass; Female; Humans; Hypoglycemic Agents; Inflammation Mediators; Italy; Leptin; Male; Metformin; Middle Aged; Myocardial Infarction; Prediabetic State; Prospective Studies; Risk Factors; Sirtuins; Time Factors; Treatment Outcome; Tumor Necrosis Factor-alpha | 2019 |
Leptin increases mitochondrial OPA1 via GSK3-mediated OMA1 ubiquitination to enhance therapeutic effects of mesenchymal stem cell transplantation.
Topics: Animals; Glycogen Synthase Kinase 3; GTP Phosphohydrolases; Humans; Indoles; Leptin; Leupeptins; Male; Maleimides; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Metalloendopeptidases; Mice; Mitochondrial Proteins; Myocardial Infarction; Proteolysis; Signal Transduction; Ubiquitination | 2018 |
Cardiac leptin overexpression in the context of acute MI and reperfusion potentiates myocardial remodeling and left ventricular dysfunction.
Acute MI induces leptin expression in the heart, however the role of myocardial leptin in cardiac ischemia and reperfusion (IR) remains unknown. To shed light on the effects of elevated levels of leptin in the myocardium, we overexpressed cardiac leptin and assessed local remodeling and myocardial function in this context.. Cardiac leptin overexpression was stimulated in mice undergoing IR by a single intraperitoneal injection of leptin antagonist (LepA). All mice exhibited a normal pattern of body weight gain. A rapid, long-term upregulation of leptin mRNA was demonstrated in the heart, adipose, and liver tissues in IR/LepA-treated mice. Overexpressed cardiac leptin mRNA extended beyond postoperative day (POD) 30. Plasma leptin peaked 7.5 hours postoperatively, especially in IR/LepA-treated mice, subsiding to normal levels by 24 hours. On POD-30 IR/LepA-treated mice demonstrated cardiomyocyte hypertrophy and perivascular fibrosis compared to IR/saline controls. Echocardiography on POD-30 demonstrated eccentric hypertrophy and systolic dysfunction in IR/LepA. We recorded reductions in Ejection Fraction (p<0.001), Fraction Shortening (p<0.01), and Endocardial Fraction Area Change (p<0.01), and an increase in Endocardial Area Change (p<0.01). Myocardial remodeling in the context of IR and cardiac leptin overexpression was associated with increased cardiac TGFβ ligand expression, activated Smad2, and downregulation of STAT3 activity.. Cardiac IR coinciding with increased myocardial leptin synthesis promotes cardiomyocyte hypertrophy and fibrosis and potentiates myocardial dysfunction. Plasma leptin levels do not reflect cardiac leptin synthesis, and may not predict leptin-related cardiovascular morbidity. Targeting cardiac leptin is a potential treatment for cardiac IR damage. Topics: Animals; Disease Models, Animal; Echocardiography; Leptin; Male; Mice; Myocardial Infarction; Myocardial Reperfusion Injury; Myocardium; Smad2 Protein; STAT3 Transcription Factor; Ventricular Dysfunction, Left; Ventricular Remodeling | 2018 |
Elevated levels of adipokines predict outcome after acute myocardial infarction: A long-term follow-up of the Glucose Tolerance in Patients with Acute Myocardial Infarction cohort.
Adiponectin and leptin are associated with insulin resistance and cardiovascular disease. Information on the prognostic value after an acute myocardial infarction is still conflicting.. Patients (n = 180) without known diabetes and with admission glucose of <11 mmol/L admitted for an acute myocardial infarction in 1998-2000 were followed for mortality and cardiovascular events (first of cardiovascular mortality/acute myocardial infarction/stroke/heart failure) until the end of 2011 (median: 11.6 years). Plasma adiponectin and leptin were related to outcome in Cox proportional-hazard regression analyses.. Median age was 64 years and 69% were male. Total mortality was 34% (n = 61) and 44% (n = 80) experienced a cardiovascular event. Adiponectin at discharge predicted cardiovascular events (hazard ratio; 95% confidence interval; 1.45; 1.02-2.07, p = 0.038), total mortality (2.53; 1.64-3.91, p < 0.001) and cancer mortality (3.64; 1.51-8.74, p = 0.004). After adjustment for age, sex, body mass index, previous myocardial infarction and heart failure, adiponectin predicted total mortality (1.79; 1.07-3.00, p = 0.027) but not cardiovascular events. High levels of leptin were associated with cardiovascular events during the first 7 years, after which the association was attenuated. Leptin did not predict total mortality.. In patients with acute myocardial infarction but without previously known diabetes, high levels of adiponectin at discharge predicted total mortality. The present results support the hypothesis that high rather than low levels of adiponectin predict mortality after acute myocardial infarction. Topics: Adiponectin; Aged; Biomarkers; Blood Glucose; Cause of Death; Chi-Square Distribution; Female; Glucose Intolerance; Humans; Insulin Resistance; Kaplan-Meier Estimate; Leptin; Logistic Models; Male; Middle Aged; Myocardial Infarction; Odds Ratio; Patient Discharge; Predictive Value of Tests; Prognosis; Proportional Hazards Models; Risk Factors; Sweden; Time Factors | 2017 |
Elective percutaneous coronary intervention leads to significant changes in serum resistin, leptin, and adiponectin levels regardless of periprocedural myocardial injury: an observational study.
Bioactive roles of adipokines in coronary atherosclerosis and acute coronary syndromes have been demonstrated previously. However, there is a lack of data regarding the relationship between serum adipokines and periprocedural myocardial injury (PMI) following elective percutaneous coronary intervention (PCI). Therefore, we aimed to investigate the association between serum adipokines and PMI related to elective PCI.. In total, 153 consecutive patients (aged 60.6±8.2 years, 98 men) with stable angina pectoris undergoing elective PCI were enrolled in this observational cross-sectional study. Serum resistin, leptin, adiponectin, and high-sensitive Troponin T (hscTnT) levels were measured immediately before PCI and after 12-h PCI. The no-injury, PMI, and type 4a myocardial infarction (type 4a MI) groups were defined as groups consisting patients with post-procedural hscTnT concentrations <14 ng/L, between 14-70 ng/L, and >70 ng/L, respectively.. Serum hscTnT, resistin, and leptin concentrations significantly (p<0.001) increased while serum adiponectin levels decreased (p<0.001) after 12-h elective PCI. However, no correlation was found between post-procedural hscTnT concentrations and resistin, leptin, and adiponectin levels. The no-injury group consisted of 65 patients (42.4%), whereas PMI and type 4a MI were observed in 70 (45.8%) and 18 (11.8%) patients, respectively. The average pre-procedural and post-procedural resistin, leptin, and adiponectin levels did not show any significant difference in the no-injury, PMI, and type 4a MI groups.. There is no correlation between serum adipokine levels and post-procedural troponin elevations reflecting PMI or type 4a MI. However, serum resistin and leptin levels increase, whereas adiponectin levels decrease significantly after elective PCI. Topics: Adiponectin; Aged; Cross-Sectional Studies; Female; Humans; Leptin; Male; Middle Aged; Myocardial Infarction; Percutaneous Coronary Intervention; Resistin | 2016 |
Human Fetuin-A Rs4918 Polymorphism and its Association with Obesity in Healthy Persons and in Patients with Myocardial Infarction in Two Hungarian Cohorts.
BACKGROUND Human fetuin A (AHSG) has been associated with the development of obesity, insulin resistance, type 2 diabetes mellitus, and atherosclerosis. Observations on the role of AHSG rs4918 single-nucleotide polymorphism are contradictory. We investigated the association between variants of rs4918 and parameters of obesity, lipid status, tumor necrosis factor-α (TNFα), adipokines (adiponectin, resistin, leptin), and insulin resistance in healthy persons and in patients with previous myocardial infarction. MATERIAL AND METHODS This was a cross-sectional study comprising cohort 1 (81 healthy individuals) and cohort 2 (157 patients with previous myocardial infarction). We used the allele-specific KASP genotyping assay to detect rs4918 polymorphism. RESULTS In cohort 1, G-nucleotide carriers had significantly lower serum TNFα, adiponectin, and higher leptin concentrations than in non-G carriers. These differences, however, were not observed in cohort 2. In cohort 2, G-carriers had lower BMI and waist circumferences than in non-G carriers. The G allele was more frequent among lean than obese patients (RR=1.067, 95%CI=1.053-2.651, p=0.015). An association between BMI and rs4918 polymorphism was observed among patients without diabetes (CC/CG/GG genotypes: p=0.003, G vs. non-G allele: p=0.008) but not in diabetics. In addition, a strong linearity between BMI and the CC/CG/GG genotypes (association value: 4.416, p=0.036) and the frequency of the G allele (7.420, p=0.006) could be identified. In cohort 2, non-obese, non-diabetic G-carriers still had lower BMI and waist circumferences than in non-G carriers. CONCLUSIONS The rs4918 minor variant is associated with lower TNFα and adiponectin, higher leptin levels in healthy persons, and more favorable anthropomorphic parameters of obesity in cohort 2. Topics: Adipokines; Adiponectin; Adult; Aged; Aged, 80 and over; alpha-2-HS-Glycoprotein; Case-Control Studies; Cohort Studies; Cross-Sectional Studies; Female; Genetic Predisposition to Disease; Humans; Hungary; Leptin; Male; Middle Aged; Myocardial Infarction; Obesity; Polymorphism, Single Nucleotide; Tumor Necrosis Factor-alpha | 2016 |
Serum leptin levels are independently related to the incidence of ischemic heart disease in a prospective study of patients with type 2 diabetes.
New and clinically useful markers of cardiovascular risk are of essence in type 2 diabetes since ischemic heart disease is a major cause of death in these patients.. We analyzed baseline data from 476 men and 244 women who participated in "Cardiovascular Risk factors in Patients with Diabetes -a Prospective study in Primary care" study. All participants had type 2 diabetes and were 55-66 years old at recruitment during year 2005 to 2008. Except for established traditional risk markers for vascular disease, we also estimated vascular complications non-invasively by performance of carotid-femoral pulse-wave velocity (PWV, with applanation-tonometry) and intima-media thickness of carotid arteries (IMT, with B-mode ultrasound). Patients were followed for incidence of ischemic heart disease mortality and morbidity until end of the year 2012, using the national Swedish Cause of Death and Hospitalization Registries.. During the follow-up period of a median of 6 years 47 men and 10 women died or were hospitalized for ischemic heart disease including myocardial infarction. Leptin levels were positively related to the hazard ratio (HR) in men (HR for each log 10 unit 4.9, CI 1.99 to 11.8) and women (HR 11.5, CI 1.47 to 89.7). Leptin predicted ischemic heart disease independently of age, HbA1c, BMI, systolic blood pressure and LDL-cholesterol/HDL-cholesterol ratio (men: HR 12.9 CI 3.2-53, women: HR 19.9, CI 1.2-327) This finding of increased risk related to high leptin levels was also statistically significant when carotid-femoral PWV and IMT were both added to the equations in men (hazard ratio 9.2 CI 2.1-41).. Our data support the use of serum leptin in type 2 diabetes to add independent prognostic information in terms of ischemic heart disease when compared with traditional cardiovascular risk factors. In the men of the cohort this prognostic information was in addition also to data on IMT and PWV, two non-invasive measurements of the extent of vascular disease. The power to detect a similar relationship in women was less strong due to lower incidence of cardiovascular disease.. ClinicalTrials.gov: NCT01049737. Topics: Carotid Arteries; Carotid Intima-Media Thickness; Cohort Studies; Diabetes Mellitus, Type 2; Female; Humans; Incidence; Leptin; Longitudinal Studies; Male; Middle Aged; Myocardial Infarction; Myocardial Ischemia; Prognosis; Proportional Hazards Models; Prospective Studies; Pulse Wave Analysis | 2015 |
[THE SYSTEM OF SOLUBLE LEPTIN RECEPTORS AND PROINFLAMMATORY FACTORS IN MYOCARDIAL INFARCTION].
The present study was motivated by the lack of data on the role ofvariations in the levels of leptin and its soluble receptors and their interaction with proinflammatory factors in the development of acute coronary syndrome. The study included patients suffering myocardial infarction with and without type 2 diabetes mellitus. Hyperleptinemia and its relationship with myocardial necrosis markers (creatine phosphokinase, creatine phosphokinase-MB, troponin) give reason to suggest the important role of leptin in the development of inflammatory process associated with myocardial infarction in patients with and without diabetes mellitus. The results of the study provide a basis for the elaboration of a new therapeutic strategy for the correction of metabolic disorders in patients with acute coronary syndrome. Topics: Aged; Diabetes Mellitus, Type 2; Female; Humans; Leptin; Male; Middle Aged; Myocardial Infarction; Receptors, Leptin | 2015 |
Long-Lived αMUPA Mice Show Attenuation of Cardiac Aging and Leptin-Dependent Cardioprotection.
αMUPA transgenic mice spontaneously consume less food compared with their wild type (WT) ancestors due to endogenously increased levels of the satiety hormone leptin. αMUPA mice share many benefits with mice under caloric restriction (CR) including an extended life span. To understand mechanisms linked to cardiac aging, we explored the response of αMUPA hearts to ischemic conditions at the age of 6, 18, or 24 months. Mice were subjected to myocardial infarction (MI) in vivo and to ischemia/reperfusion ex vivo. Compared to WT mice, αMUPA showed functional and histological advantages under all experimental conditions. At 24 months, none of the WT mice survived the first ischemic day while αMUPA mice demonstrated 50% survival after 7 ischemic days. Leptin, an adipokine decreasing under CR, was consistently ~60% higher in αMUPA sera at baseline. Leptin levels gradually increased in both genotypes 24h post MI but were doubled in αMUPA. Pretreatment with leptin neutralizing antibodies or with inhibitors of leptin signaling (AG-490 and Wortmannin) abrogated the αMUPA benefits. The antibodies also reduced phosphorylation of the leptin signaling components STAT3 and AKT specifically in the αMUPA myocardium. αMUPA mice did not show elevation in adiponectin, an adipokine previously implicated in CR-induced cardioprotection. WT mice treated for short-term CR exhibited cardioprotection similar to that of αMUPA, however, along with increased adiponectin at baseline. Collectively, the results demonstrate a life-long increased ischemic tolerance in αMUPA mice, indicating the attenuation of cardiac aging. αMUPA cardioprotection is mediated through endogenous leptin, suggesting a protective pathway distinct from that elicited under CR. Topics: Adipokines; Animals; Biomarkers; Cellular Senescence; Disease Models, Animal; Echocardiography; Heart Ventricles; Kaplan-Meier Estimate; Leptin; Mice; Mice, Transgenic; Myocardial Infarction; Myocardium; Proto-Oncogene Proteins c-akt; Signal Transduction; STAT3 Transcription Factor; Tyrphostins; Ventricular Function | 2015 |
Hypoxia preconditioned mesenchymal stem cells prevent cardiac fibroblast activation and collagen production via leptin.
Activation of cardiac fibroblasts into myofibroblasts constitutes a key step in cardiac remodeling after myocardial infarction (MI), due to interstitial fibrosis. Mesenchymal stem cells (MSCs) have been shown to improve post-MI remodeling an effect that is enhanced by hypoxia preconditioning (HPC). Leptin has been shown to promote cardiac fibrosis. The expression of leptin is significantly increased in MSCs after HPC but it is unknown whether leptin contributes to MSC therapy or the fibrosis process. The objective of this study was to determine whether leptin secreted from MSCs modulates cardiac fibrosis.. Cardiac fibroblast (CF) activation was induced by hypoxia (0.5% O2). The effects of MSCs on fibroblast activation were analyzed by co-culturing MSCs with CFs, and detecting the expression of α-SMA, SM22α, and collagen IαI in CFs by western blot, immunofluorescence and Sirius red staining. In vivo MSCs antifibrotic effects on left ventricular remodeling were investigated using an acute MI model involving permanent ligation of the left anterior descending coronary artery.. Co-cultured MSCs decreased fibroblast activation and HPC enhanced the effects. Leptin deficit MSCs from Ob/Ob mice did not decrease fibroblast activation. Consistent with this, H-MSCs significantly inhibited cardiac fibrosis after MI and mediated decreased expression of TGF-β/Smad2 and MRTF-A in CFs. These effects were again absent in leptin-deficient MSCs.. Our data demonstrate that activation of cardiac fibroblast was inhibited by MSCs in a manner that was leptin-dependent. The mechanism may involve blocking TGF-β/Smad2 and MRTF-A signal pathways. Topics: Animals; Cell Differentiation; Collagen; Gene Expression; Hypoxia; Ischemic Preconditioning, Myocardial; Leptin; Mesenchymal Stem Cells; Mice; Myocardial Infarction; Myofibroblasts; Signal Transduction; Smad2 Protein; Trans-Activators; Transforming Growth Factor beta; Ventricular Remodeling | 2014 |
Association of leptin in periodontitis and acute myocardial infarction.
Serum leptin concentrations are reported to be elevated in patients with periodontal diseases and may have a modulating role in cardiovascular diseases. Serum leptin concentrations have not been assessed in periodontitis associated with acute myocardial infarction (AMI) to date. The purpose of this study was to assess the concentration of serum leptin in periodontitis associated with AMI.. A cross-sectional clinical study was conducted comprising a sample size of 120 participants divided into four groups (n = 30 each) based on their clinical signs: 1) control; 2) AMI; 3) generalized chronic periodontitis (GCP); and 4) GCP + AMI. Body mass index (BMI) was calculated and recorded for all the subjects based on BMI chart of the World Health Organization. After thorough clinical and oral examination, plaque index (PI), gingival index (GI), probing depth (PD), and clinical attachment loss (AL) were recorded. In addition, 2 mL venous blood was collected by venipuncture from all participants to determine serum leptin concentration using the enzyme-linked immunosorbent assay method.. A strong correlation of serum leptin concentration to BMI was observed in AMI, GCP, and GCP + AMI groups. Serum leptin levels were significantly elevated in AMI, GCP, and GCP + AMI groups compared to the control group. Significant associations between serum leptin concentration and PI, GI, PD, and AL were also seen in the GCP group. PI, GI, PD, and AL were statistically significantly elevated in GCP + AMI and AMI groups.. Elevated serum leptin concentration was associated with increased BMI, GCP, and AMI and may serve as a risk marker for these conditions. Topics: Adult; Biomarkers; Body Mass Index; Cross-Sectional Studies; Dental Plaque Index; Female; Humans; Leptin; Male; Middle Aged; Myocardial Infarction; Periodontal Attachment Loss; Periodontal Index; Periodontal Pocket; Periodontitis | 2014 |
Impaired mitochondrial biogenesis due to dysfunctional adiponectin-AMPK-PGC-1α signaling contributing to increased vulnerability in diabetic heart.
Impaired mitochondrial biogenesis causes skeletal muscle damage in diabetes. However, whether and how mitochondrial biogenesis is impaired in the diabetic heart remains largely unknown. Whether adiponectin (APN), a potent cardioprotective molecule, regulates cardiac mitochondrial function has also not been previously investigated. In this study, electron microscopy revealed significant mitochondrial disorders in ob/ob cardiomyocytes, including mitochondrial swelling and cristae disorientation and breakage. Moreover, mitochondrial biogenesis of ob/ob cardiomyocytes is significantly impaired, as evidenced by reduced Ppargc-1a/Nrf-1/Tfam mRNA levels, mitochondrial DNA content, ATP content, citrate synthase activity, complexes I/III/V activity, AMPK phosphorylation, and increased PGC-1α acetylation. Since APN is an upstream activator of AMPK and APN plasma levels are significantly reduced in ob/ob mice, we further tested the hypothesis that reduced APN in ob/ob mice is causatively related to mitochondrial biogenesis impairment. One week of APN treatment of ob/ob mice activated AMPK, reduced PGC-1α acetylation, increased mitochondrial biogenesis, and attenuated mitochondrial disorders. In contrast, knocking out APN inhibited AMPK-PGC-1α signaling and impaired both mitochondrial biogenesis and function. The ob/ob mice exhibited lower survival rates and exacerbated myocardial injury after MI, when compared to controls. APN supplementation improved mitochondrial biogenesis and attenuated MI injury, an effect that was almost completely abrogated by the AMPK inhibitor compound C. In high glucose/high fat treated neonatal rat ventricular myocytes, siRNA-mediated knockdown of PGC-1α blocked gAd-enhanced mitochondrial biogenesis and function and attenuated protection against hypoxia/reoxygenation injury. In conclusion, hypoadiponectinemia impaired AMPK-PGC-1α signaling, resulting in dysfunctional mitochondrial biogenesis that constitutes a novel mechanism for rendering diabetic hearts more vulnerable to enhanced MI injury. Topics: Acetylation; Adenosine Triphosphate; Adiponectin; AMP-Activated Protein Kinases; Animals; Animals, Newborn; Cells, Cultured; Diabetes Complications; Disease Models, Animal; DNA-Binding Proteins; DNA, Mitochondrial; Electron Transport Chain Complex Proteins; Energy Metabolism; High Mobility Group Proteins; Leptin; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Microscopy, Electron; Mitochondria, Heart; Mitochondrial Swelling; Mitochondrial Turnover; Myocardial Infarction; Myocardium; Nuclear Respiratory Factor 1; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Rats; Rats, Sprague-Dawley; RNA Interference; RNA-Binding Proteins; RNA, Messenger; Signal Transduction; Time Factors; Trans-Activators; Transcription Factors; Transfection | 2013 |
[The detection of leptin and metabolic markers of insulin resistance in patients with myocardial infarction].
The shortage of data concerning the character of changes of leptin concentration and its role information of insulin resistance under development of acute coronary events determined the appropriateness of the present study. The cardiac infarction patients with and without diabetes type II were examined. The identified hyperleptinemia, its relationship with basal and post-prandial hyperglycemia and with increase of C-peptide concentration and free fatty acids made possible to consider leptin both as one of the important components in the series of carbohydrate and lipid metabolism disorders and the additional marker of development of insulin resistance under cardiac infarction. These study results can be applied to patients with diabetes anamnesis and to patients without this concomitant pathology. The study results can be used as a foundation for new diagnostic and therapy tactics of metabolic disorders correction in patients with acute coronary vascular pathology. Topics: Aged; Biomarkers; Blood Glucose; Body Mass Index; C-Peptide; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Humans; Insulin; Insulin Resistance; Leptin; Male; Middle Aged; Myocardial Infarction | 2013 |
Intestinal microbiota determine severity of myocardial infarction in rats.
Signals from the intestinal microbiota are important for normal host physiology; alteration of the microbiota (dysbiosis) is associated with multiple disease states. We determined the effect of antibiotic-induced intestinal dysbiosis on circulating cytokine levels and severity of ischemia/reperfusion injury in the heart. Treatment of Dahl S rats with a minimally absorbed antibiotic vancomycin, in the drinking water, decreased circulating leptin levels by 38%, resulted in smaller myocardial infarcts (27% reduction), and improved recovery of postischemic mechanical function (35%) as compared with untreated controls. Vancomycin altered the abundance of intestinal bacteria and fungi, measured by 16S and 18S ribosomal DNA quantity. Pretreatment with leptin (0.12 μg/kg i.v.) 24 h before ischemia/reperfusion abolished cardioprotection produced by vancomycin treatment. Dahl S rats fed the commercially available probiotic product Goodbelly, which contains the leptin-suppressing bacteria Lactobacillus plantarum 299v, also resulted in decreased circulating leptin levels by 41%, smaller myocardial infarcts (29% reduction), and greater recovery of postischemic mechanical function (23%). Pretreatment with leptin (0.12 μg/kg i.v.) abolished cardioprotection produced by Goodbelly. This proof-of-concept study is the first to identify a mechanistic link between changes in intestinal microbiota and myocardial infarction and demonstrates that a probiotic supplement can reduce myocardial infarct size. Topics: Animals; Anti-Bacterial Agents; Cytokines; Drinking Water; Humans; Intestines; Leptin; Metagenome; Myocardial Infarction; Myocardial Reperfusion Injury; Probiotics; Rats; Rats, Inbred Dahl; Vancomycin | 2012 |
Elevated serum leptin levels in patients with acute myocardial infarction; correlation with coronary angiographic and echocardiographic findings.
To assess the relationship between serial serum leptin levels in patients with acute myocardial infarction (AMI) who received thrombolysis and the degree of coronary atherosclerosis, coronary reperfusion, echocardiographic findings, and clinical outcome. 51 consecutive patients presenting with AMI were studied. Clinical characteristics including age, sex, body mass index (BMI) and cardiovascular risk factors were recorded. Serial serum leptin levels at the time of admission and subsequently at 0, 6, 12, 24, 36, 60 hours afterwards were obtained. Coronary angiography was performed in 34 patients; the relation between serum leptin levels and evidence of coronary reperfusion as well as the extent of coronary atherosclerosis according to the coronary artery surgery study classification (CASS) were evaluated. Echocardiographic evaluation was performed in all patients. 36 matched patients were enrolled as control group who had serum leptin level 9.4 ± 6.5 ng/ml.. The patients mean age was 50.5 ± 10.6 years. There were 47 males and 3 females. 37.1% were diabetics, 23.5% were hypertensive, 21.6% were dyslipidemic and 22.7% were obese (BMI ≥ 30). Leptin concentrations (ng/ml) increased and peaked at the 4th sample (36 hrs) after admission (mean ± SD) sample (1) =9.55 ± 7.4, sample (2) =12.9 ± 8.4, sample (3) =13.8 ± 10.4, sample (4) =18.9 ± 18.1, sample (5) =11.4 ± 6.5, sample (6) =10.8 ± 8.9 ng/ml. There was a significant correlation between serum leptin and BMI (r = 0.342; p = 0.03). Leptin levels correlated significantly to creatine kinase level on the second day (r = 0.43, p ≤ 0.01). Significant correlation of mean serum leptin with the ejection fraction (P < 0.05) was found. No difference in timing of peak serum leptin between patients who achieved coronary reperfusion vs. those who did not (p = 0.8). There was a trend for an increase in the mean serum leptin levels with increasing number of diseased vessels. There was no correlation between serum leptin levels and outcome neither during the hospitalization nor at 9 months follow up.. Serum leptin levels increase after myocardial infarction. Serum leptin level may be a predictor of the left ventricular ejection fraction and the degree of atherosclerosis but not of coronary reperfusion. Topics: Acute Disease; Adult; Body Mass Index; Case-Control Studies; Coronary Angiography; Coronary Artery Disease; Creatine Kinase; Echocardiography; Female; Fibrinolytic Agents; Humans; Leptin; Lipoproteins; Male; Middle Aged; Myocardial Infarction; Myocardial Reperfusion; Risk Factors; Treatment Outcome; Ventricular Function, Left | 2012 |
Angiotensin-converting enzyme inhibition and food restriction in diabetic mice do not correct the increased sensitivity for ischemia-reperfusion injury.
The number of patients with diabetes or the metabolic syndrome reaches epidemic proportions. On top of their diabetic cardiomyopathy, these patients experience frequent and severe cardiac ischemia-reperfusion (IR) insults, which further aggravate their degree of heart failure. Food restriction and angiotensin-converting enzyme inhibition (ACE-I) are standard therapies in these patients but the effects on cardiac IR injury have never been investigated. In this study, we tested the hypothesis that 1° food restriction and 2° ACE-I reduce infarct size and preserve cardiac contractility after IR injury in mouse models of diabetes and the metabolic syndrome.. C57Bl6/J wild type (WT) mice, leptin deficient ob/ob (model for type II diabetes) and double knock-out (LDLR-/-;ob/ob, further called DKO) mice with combined leptin and LDL-receptor deficiency (model for metabolic syndrome) were used. The effects of 12 weeks food restriction or ACE-I on infarct size and load-independent left ventricular contractility after 30 min regional cardiac ischemia were investigated. Differences between groups were analyzed for statistical significance by Student's t-test or factorial ANOVA followed by a Fisher's LSD post hoc test.. Infarct size was larger in ob/ob and DKO versus WT. Twelve weeks of ACE-I improved pre-ischemic left ventricular contractility in ob/ob and DKO. Twelve weeks of food restriction, with a weight reduction of 35-40%, or ACE-I did not reduce the effect of IR.. ACE-I and food restriction do not correct the increased sensitivity for cardiac IR-injury in mouse models of type II diabetes and the metabolic syndrome. Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Biomarkers; Caloric Restriction; Diabetes Mellitus, Type 2; Disease Models, Animal; Leptin; Metabolic Syndrome; Mice; Mice, Inbred C57BL; Mice, Knockout; Mice, Obese; Myocardial Contraction; Myocardial Infarction; Myocardial Reperfusion Injury; Myocardium; Receptors, LDL; Time Factors; Ventricular Function, Left; Ventricular Pressure | 2012 |
Serum ghrelin level and TNF-α/ghrelin ratio in patients with previous myocardial infarction.
Studies investigating serum ghrelin level in atherosclerosis yielded contradictory results. Interaction of ghrelin with adipocytokines is obscure in cardiovascular diseases. We undertook this study to determine which molecules influence ghrelin level and to see whether post-myocardial infarction (MI) patients have decreased ghrelin levels.. In this cross-sectional study, acyl-ghrelin concentration was determined by radioimmunoassay in sera of 171 patients (ages 62 ± 6 years, mean ± SD) with previous MI and 81 age-matched referent subjects. We evaluated the associations of ghrelin with insulin, adiponectin, leptin, resistin, fetuin-A and tumor necrosis factor-alpha (TNF-α).. Patients had lower ghrelin levels compared to referent subjects (240.55 ± 59.33 vs. 337.96 ± 30.75 pg/mL, p <0.001) even after excluding diabetic and obese patients (240.63 ± 54.08 vs. 337.96 ± 30.75, p <0.001). In multivariate analysis, insulin (β = -0.327, p <0.001) and adiponectin (β = 0.301, p <0.001) determined ghrelin level (R(2) = 0.199, p <0.001). There was no association between ghrelin and TNF-α levels. In discriminant analysis using ghrelin, adiponectin, leptin, fetuin-A, resistin and TNF-α, the structure matrix revealed ghrelin and TNF-α as strongest predictors for belonging to the patient group (0.760 and -0.569, respectively). Using these two parameters, 89.7% of cases were correctly classified. Subjects with high TNF-α/ghrelin ratio had 11.25 times higher chance for belonging to the patient group (95% CI 5.80-21.80; χ(2) (1) = 215.6, p <0.001). Acylated ghrelin levels are decreased in patients with coronary atherosclerosis, independently of body weight and the presence of type 2 diabetes mellitus. Ghrelin level is determined by elevated insulin and decreased adiponectin levels. Ghrelin alone or in combination with TNF-α may prove to be a novel indicator of coronary atherosclerosis. Topics: Adiponectin; Aged; alpha-2-HS-Glycoprotein; Atherosclerosis; Blood Glucose; Body Weight; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Female; Ghrelin; Humans; Insulin; Leptin; Male; Middle Aged; Myocardial Infarction; Resistin; Tumor Necrosis Factor-alpha | 2012 |
Inhibition of cardiac leptin expression after infarction reduces subsequent dysfunction.
Leptin is known to exert cardiodepressive effects and to induce left ventricular (LV) remodelling. Nevertheless, the autocrine and/or paracrine activities of this adipokine in the context of post-infarct dysfunction and remodelling have not yet been elucidated. Therefore, we have investigated the evolution of myocardial leptin expression following myocardial infarction (MI) and evaluated the consequences of specific cardiac leptin inhibition on subsequent LV dysfunction. Anaesthetized rats were subjected to temporary coronary occlusion. An antisense oligodesoxynucleotide (AS ODN) directed against leptin mRNA was injected intramyocardially along the border of the infarct 5 days after surgery. Cardiac morphometry and function were monitored by echocardiography over 11 weeks following MI. Production of myocardial leptin and pro-inflammatory cytokines interleukin (IL)-1β and IL-6 were assessed by ELISA. Our results show that (1) cardiac leptin level peaks 7 days after reperfused MI; (2) intramyocardial injection of leptin-AS ODN reduces early IL-1β and IL-6 overexpression and markedly protects contractile function. In conclusion, our findings demonstrate that cardiac leptin expression after MI could contribute to the evolution towards heart failure through autocrine and/or paracrine actions. The detrimental effect of leptin could be mediated by pro-inflammatory cytokines such as IL-1β and IL-6. Our data could constitute the basis of new therapeutic approaches aimed to improve post-MI outcome. Topics: Animals; DNA, Antisense; Echocardiography; Enzyme-Linked Immunosorbent Assay; Heart; Interleukin-1beta; Interleukin-6; Leptin; Male; Myocardial Infarction; Myocardium; Rats; Rats, Wistar; Time Factors; Ventricular Dysfunction, Left | 2011 |
The cellular specificity of leptin-mediated actions in the infarcted heart.
Topics: Animals; Leptin; Mice; Mice, Knockout; Models, Cardiovascular; Myocardial Infarction; Myocytes, Cardiac; Receptors, Leptin; Signal Transduction; Ventricular Remodeling | 2011 |
Association of low leptin with cardiovascular events and mortality in patients with stable coronary artery disease: the Heart and Soul Study.
Leptin is an adipokine with both protective and harmful effects on the cardiovascular (CV) system. Prior studies evaluating the association between leptin and CV outcomes have yielded conflicting results. Thus, we sought to investigate the relationship between leptin and CV events and mortality in patients with chronic stable coronary artery disease (CAD).. We performed a prospective cohort study of 981 outpatients with stable CAD. Leptin levels were measured in fasting venous samples at baseline. We used proportional hazards models to evaluate the association of baseline leptin with subsequent CV events (myocardial infarction, stroke, transient ischemic attack) and death.. During a mean follow-up of 6.2±2.1 years, there were 304 deaths, 112 myocardial infarctions, and 52 strokes/TIAs. In models adjusted for age, sex, and race, low leptin was associated with a 30% increased risk of the combined outcome (HR 1.30, CI 1.05-1.59, p=0.01). After further adjustment for obesity, traditional CV risk factors and biomarkers, low leptin remained associated with a 37% increased risk of events (HR 1.37, CI 1.06-1.76, p=0.02).. Low leptin is associated with increased CV events and mortality in patients with stable coronary artery disease. This association is independent of known factors affecting leptin levels, including gender and obesity. Topics: Aged; Biomarkers; Cardiovascular Diseases; Chi-Square Distribution; Chronic Disease; Coronary Artery Disease; Down-Regulation; Female; Humans; Ischemic Attack, Transient; Kaplan-Meier Estimate; Leptin; Male; Middle Aged; Myocardial Infarction; Proportional Hazards Models; Prospective Studies; Risk Assessment; Risk Factors; San Francisco; Stroke | 2011 |
Receptor-mediated activation of ceramidase activity initiates the pleiotropic actions of adiponectin.
The adipocyte-derived secretory factor adiponectin promotes insulin sensitivity, decreases inflammation and promotes cell survival. No unifying mechanism has yet explained how adiponectin can exert such a variety of beneficial systemic effects. Here, we show that adiponectin potently stimulates a ceramidase activity associated with its two receptors, AdipoR1 and AdipoR2, and enhances ceramide catabolism and formation of its antiapoptotic metabolite--sphingosine-1-phosphate (S1P)--independently of AMP-dependent kinase (AMPK). Using models of inducible apoptosis in pancreatic beta cells and cardiomyocytes, we show that transgenic overproduction of adiponectin decreases caspase-8-mediated death, whereas genetic ablation of adiponectin enhances apoptosis in vivo through a sphingolipid-mediated pathway. Ceramidase activity is impaired in cells lacking both adiponectin receptor isoforms, leading to elevated ceramide levels and enhanced susceptibility to palmitate-induced cell death. Combined, our observations suggest a unifying mechanism of action for the beneficial systemic effects exerted by adiponectin, with sphingolipid metabolism as its core upstream signaling component. Topics: Adenylate Kinase; Adiponectin; Animals; Apoptosis; Calcium-Calmodulin-Dependent Protein Kinase Kinase; Ceramidases; Ceramides; Enzyme Activation; Gene Expression Regulation; Humans; Insulin; Kinetics; Leptin; Mice; Mice, Obese; Myocardial Infarction; Myocytes, Cardiac; Receptors, Adiponectin | 2011 |
Inflammatory biomarkers in patients with posttraumatic stress disorder caused by myocardial infarction and the role of depressive symptoms.
Inflammation might link posttraumatic stress disorder (PTSD) with an increased risk of cardiovascular events. We explored the association between PTSD and inflammatory biomarkers related to cardiovascular morbidity and the role of co-morbid depressive symptoms in this relationship.. We investigated 15 patients with interviewer-rated PTSD caused by myocardial infarction (MI) and 29 post-MI patients with no PTSD. All patients completed the depression subscale of the Hospital Anxiety and Depression Scale and had blood collected to determine inflammatory markers of increased cardiovascular risk.. Controlling for demographic and medical covariates, patients with PTSD had higher leptin levels than patients with no PTSD (p = 0.038, explained variance 10.4%); this difference became nonsignificant when controlling for depressive symptoms. After controlling for depressive symptoms, PTSD patients had higher interleukin-6 (p = 0.041; explained variance 10%), lower C-reactive protein (p = 0.022, explained variance 12.1%), and lower soluble CD40 ligand (p = 0.016, explained variance 13.4%) than patients without PTSD. After controlling for PTSD status, depressive symptoms correlated with soluble CD40 ligand (r = 0.45, p = 0.002) and with C-reactive protein (r = 0.29, p < 0.07).. The findings provide further evidence for altered inflammation in PTSD. Comorbid depressive symptoms ought to be considered to disentangle the unique associations of PTSD caused by MI and systemic inflammation. Topics: Aged; Biomarkers; CD40 Ligand; Comorbidity; Depressive Disorder; Female; Humans; Inflammation; Inflammation Mediators; Interleukin-6; Leptin; Male; Middle Aged; Myocardial Infarction; Neuropsychological Tests; Stress Disorders, Post-Traumatic; Surveys and Questionnaires | 2010 |
Leptin in acute myocardial infarction and period of convalescence in patients with type 2 diabetes mellitus.
Leptin is a protein produced in adipose tissue and takes part in angiogenesis and atherogenesis. Leptin is associated with development of type 2 diabetes and cardiovascular disease.. To evaluate leptin concentrations in acute myocardial infarction and in the period of convalescence in patients with type 2 diabetes mellitus.. Coronary angiography was performed in 58 patients with acute myocardial infarction. The study group comprised 35 patients with type 2 diabetes mellitus (DM) (25 men, 10 women, mean age 63.8 + or - 11.5 years) and 23 non-diabetic subjects (17 men, 6 women, mean age 58.6 + or - 9.9 years) - the control group. All patients underwent medical examination and body mass indices (BMI) as well as waist/hip ratios (WHR) were calculated. Venous blood was collected after 24 hours of admission (second day), on day 5 and three weeks after admission.. Leptin level was significantly associated with BMI (DM: r = 0.46, p = 0.005; control group: r = 0.67, p < 0.01), and hip circumference (DM: r = 0.28, p = 0.09; control group: r = 0.41, p = 0.04). Plasma leptin levels in women with type 2 diabetes were higher than in men (32.1 + or - 11.7 microg/mL vs 12.7 + or - 11.2 microg/mL, p < 0.01). Plasma leptin levels were significantly lower in non-diabetics compared to diabetic patients. Plasma leptin levels in diabetic patients were significantly higher in the acute phase of myocardial infarction than in the period of convalescence (18.3 + or - 14.3 microg/mL, 16.1 + or - 12.8 microg/mL, 14.8 + or - + or - 11.2 microg/mL, p = 0.02) but not in the control group (10.6 + or - 8.2 microg/mL, 10.0 + or - 7.3 microg/mL, 9.6 + or - 7.0 microg/mL, NS).. Plasma leptin levels in diabetic patients were significantly higher in the acute myocardial infarction than in the period of convalescence. These findings suggests that leptin may play an important role in the metabolic changes taking place during the first days of myocardial infarction. Topics: Body Mass Index; Convalescence; Coronary Angiography; Diabetes Mellitus, Type 2; Female; Humans; Leptin; Male; Middle Aged; Myocardial Infarction; Sex Characteristics | 2010 |
[Comment to article Leptin in acute myocardial infarction and period of convalescence in patients with type 2 diabetes mellitus].
Topics: Body Mass Index; Convalescence; Diabetes Mellitus, Type 2; Female; Humans; Leptin; Male; Middle Aged; Myocardial Infarction | 2010 |
Leptin predicts diabetes but not cardiovascular disease: results from a large prospective study in an elderly population.
To clarify the association of circulating levels of leptin with risk for cardiovascular disease (CVD) events and new-onset diabetes in men and women.. We related baseline leptin levels to CVD events (n = 864) and incident diabetes (n = 289) in an elderly population (n = 5,672) over 3.2 years of follow-up.. In treatment-, age-, and country-adjusted models, leptin was not associated with risk of CVD in men (hazard ratio 1.02 [95% CI 0.90-1.16] per unit log-leptin increase) or women (1.05 [0.91-1.20]) but was associated with risk of diabetes in men (2.75 [2.14-3.52]) and women (1.54 [1.22-1.94]). After adjusting for classic risk factors and BMI, C-reactive protein, and glucose, the diabetes association retained significance in men (1.85 [1.30-2.63]) but not in women (0.89 [0.64-1.26]).. Leptin, similar to other markers of adiposity in general, is more strongly related to risk of diabetes than CVD in the elderly. Topics: Aged; Aged, 80 and over; Biomarkers; Cardiovascular Diseases; Diabetes Mellitus; Female; Humans; Ireland; Leptin; Male; Myocardial Infarction; Netherlands; Proportional Hazards Models; Prospective Studies; Risk Assessment; Risk Factors; Scotland; Stroke | 2009 |
Factors associated with C-reactive protein at the early stage of acute myocardial infarction in men.
Elevation of C-reactive protein (CRP) is associated with acute coronary events. CRP is related to cardiovascular risk factors and adipokines. The aim of the study was to reveal the factors associated with elevated CRP levels in patients with ST-segment elevation acute myocardial infarction (STEMI). As there are sex-related differences in plasma levels of CRP and adipokines, our study was designed for males.. Seventy men admitted within the initial 6 hours of STEMI were categorized into 4 groups according to the quartile of CRP. Clinical data and laboratory measurements were analyzed.. Anthropometric measurements, glucose at admission, resistin, and leptin were significantly higher, and adiponectin lower with the increase of CRP quartile. A significant positive correlation between CRP and body mass index, waist circumference, glucose at admission, resistin, and leptin and a negative relation of CRP to HDL-cholesterol and adiponectin were observed. In univariate logistic regression analysis, variables associated with a level of CRP above the fourth quartile were history of angina, obesity, diabetes, glucose at admission, resistin, leptin, and adiponectin, and independent predictors were glucose at admission and resistin. To predict the elevated CRP level the optimal cut-off for glucose at admission was 144 mg/dL (sensitivity 84%, specificity 86%) and for resistin was 21.5 ng/mL (sensitivity 79%, specificity 71%).. Glucose at admission and resistin are independently associated with elevated levels of CRP in men during the early stage of STEMI. Topics: Adiponectin; Angioplasty, Balloon, Coronary; Biomarkers; Blood Glucose; Body Mass Index; C-Reactive Protein; Humans; Leptin; Lipids; Logistic Models; Male; Myocardial Infarction; Predictive Value of Tests; Resistin; Risk Assessment; Risk Factors; Sensitivity and Specificity; Time Factors; Up-Regulation; Waist Circumference | 2009 |
Leptin attenuates cardiac apoptosis after chronic ischaemic injury.
We have previously shown that activation of leptin signalling in the heart reduces cardiac morbidity and mortality after myocardial infarction (MI). In the present study, we tested the hypothesis that leptin signalling limits cardiac apoptosis after MI through activation of signal transducer and activator of transcription (STAT)-3 responsive anti-apoptotic genes, including B-cell lymphoma (bcl)-2 and survivin, that serve to downregulate the activity of caspase-3.. Hearts from C57BL/6J and three groups of leptin-deficient Ob/Ob mice (food-restricted, ad libitum, and leptin-repleted) were examined 4 weeks after permanent left coronary artery ligation or sham operation. Inflammatory and apoptotic cell number was determined in cardiac sections by immunostaining. Expression of cardiac bcl-2, survivin, and pro and active caspase-3 was determined and correlated with in vitro caspase-3 activity. In the absence of MI, both lean and obese leptin-deficient mice exhibited increased cardiac apoptosis compared with wild-type mice. After MI, the highest rates of apoptosis were seen in the infarcted tissue of lean and obese Ob/Ob mice. Further, leptin-deficient hearts, as well as hearts from wild-type mice treated with the STAT-3 inhibitor WP1066, exhibited blunted anti-apoptotic bcl-2 and survivin gene expression, and increased caspase-3 protein expression and activity. The increased caspase-3 activity and apoptosis in hearts of leptin-deficient mice after MI was significantly attenuated in Ob/Ob mice replete with leptin, reducing apoptosis to levels comparable to that observed in wild-type mice after MI.. These results demonstrate that intact leptin signalling post-MI acts through STAT-3 to increase anti-apoptotic bcl-2 and survivin gene expression and reduces caspase-3 activity, consistent with a cardioprotective role of leptin in the setting of chronic ischaemic injury. Topics: Animals; Apoptosis; bcl-Associated Death Protein; Caspase 3; Chronic Disease; Coronary Vessels; Disease Models, Animal; Inflammation; Inhibitor of Apoptosis Proteins; Leptin; Ligation; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Microtubule-Associated Proteins; Myocardial Infarction; Myocardium; Phosphorylation; Proto-Oncogene Proteins c-bcl-2; Pyridines; Repressor Proteins; Signal Transduction; STAT3 Transcription Factor; Survivin; Tyrphostins | 2009 |
The cardioprotective actions of leptin are lost in the Zucker obese (fa/fa) rat.
Protection against myocardial ischemia-reperfusion injury, including that induced by leptin, involves activation of the reperfusion injury salvage kinase pathway and inhibition of the mitochondrial permeability transition pore. In the current study, we explored the mechanisms underlying leptin-induced cardioprotection further with reference to the leptin receptor (OB-R) and obesity. We examined hearts from Wistar and Zucker lean rats that express functional OB-R and Zucker obese (fa/fa) rats with nonfunctional OB-R. In Langendorff experiments, leptin (10 nM) caused significant reductions in infarct size in hearts from Wistar (leptin treated, 32.4% +/- 3.9% vs. control, 53.2% +/- 3.2%, P < 0.01) and Zucker lean animals (leptin treated, 25.2% +/- 3.7% vs. control, 53.9% +/- 11.3%, P < 0.01). By contrast, hearts from (fa/fa) did not exhibit significant decreases in infarct size. Leptin increased p44 and p42 phosphorylation in Wistar rat hearts by 103.9% (P < 0.05) and 157.3% (P < 0.001), respectively, and by 97.0% (P < 0.05) and 158.1% (P < 0.05) in hearts from Zucker lean rats. Akt/serine-473 phosphorylation was increased in Wistar hearts by 96.7% (P < 0.05), whereas Akt/threonine-308 phosphorylation was elevated by 43.9% (P < 0.05) in Zucker lean rat hearts. Leptin did not influence Akt or p44/42 phosphorylation in (fa/fa) animals. On leptin treatment, mitochondrial permeability transition pore opening was delayed by 43% (P < 0.01) and 30.9% (P < 0.01), respectively, in cardiomyocytes from Wistar and Zucker lean rat hearts but not in cardiomyocytes from (fa/fa). This study provides the first evidence that myocardial sensitivity to the tissue preserving actions of leptin is influenced by adiposity and OB-R status. Topics: Animals; Cardiotonic Agents; Heart Ventricles; Leptin; Male; Mitochondrial Membrane Transport Proteins; Mitochondrial Permeability Transition Pore; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Models, Biological; Myocardial Infarction; Myocardial Reperfusion Injury; Myocytes, Cardiac; Obesity; Phosphorylation; Proto-Oncogene Proteins c-akt; Rats; Rats, Zucker; Receptors, Leptin; Serine | 2009 |
Myocardial ischemic-reperfusion injury in a rat model of metabolic syndrome.
Hearts of NaCl-induced hypertensive-glucose intolerant (HGI) rats develop reduced infarcts after ischemia-reperfusion injury (IRI) than their hypertensive (H) counterparts. Because high intake of saturated fat is a major risk factor for ischemic heart disease, we tested the hypothesis that chronic (18 weeks) consumption of a high saturated fat diet increases susceptibility to IRI, an effect more marked in the HGI rats than in the H rats. The fat-fed H (HFAT) rat displayed significantly higher body weight and plasma leptin content compared to the H, HGI, or fat-fed HGI (HGIFAT) rats which all showed similar values. In contrast, plasma triglyceride concentration was significantly higher in the HGIFAT rat than in the other three groups. Plasma insulin concentration was similar in the two H groups but higher than that of the two HGI groups. Compared to the H rat, the HGI rat was markedly glucose intolerant, with fat feeding causing comparable worsening of glucose intolerance in each group. The HGIFAT rats displayed a reduction in baseline myocardial contractility and relaxation and a higher end-diastolic pressure compared to the other three groups. Infarct size was significantly lower in the HGI rats than in the H rats. Although fat feeding did not affect infarct size of the H rat, it worsened that of the HGIFAT rat thereby abrogating the differential that existed between the H and HGI rats. In conclusion, excess fat feeding impairs myocardial function of HGI rats and increases their susceptibility to IRI. These findings are of relevance to the metabolic syndrome that manifests as a cluster of insulin resistance, dyslipidemia, and systemic hypertension. Topics: Animals; Blood Glucose; Blood Pressure; Body Weight; Dietary Fats; Disease Models, Animal; Glucose Intolerance; Hypertension; Insulin; Leptin; Male; Metabolic Syndrome; Myocardial Contraction; Myocardial Infarction; Myocardial Reperfusion Injury; Rats; Rats, Inbred WKY; Sodium Chloride, Dietary; Streptozocin; Time Factors; Triglycerides; Ventricular Pressure | 2008 |
Value of blood adipose tissue hormones concentration--adiponectin, resistin and leptin in the prediction of major adverse cardiac events (MACE) in 1-year follow-up after primary percutaneous coronary intervention in ST-segment elevation acute myocardial i
The objective of the study was to assess the impact of adipokines on the future major adverse cardiac events (MACE) in patients with acute myocardial infarction.. Subjects were 77 men with first, ST-segment elevation acute myocardial infarction undergoing primary percutaneous coronary intervention in whom data were available after one year follow-up. Baseline clinical and angiographic data were collected, blood level of C-reactive protein, uric acid, fasting glucose, lipid profile, adiponectin, resistin and leptin and left ventricular ejection fraction on echocardiography were assessed. MACE was defined as cardiac death, nonfatal myocardial infarction, hospitalization for angina or heart failure.. 12% of patients experienced MACE. As revealed by univariate logistic regression analysis predictors of MACE were diabetes, multivessel disease, ejection fraction, blood C-reactive protein and adiponectin level. In multivariable analysis diabetes (OR=22.19, 95%CI 1.22-402.19; p=0.0360), lower left ventricular ejection fraction (OR=0.78, 95%CI 0.63-0.98; p=0.0298) and lower adiponectin level (OR=0.19, 95%CI 0.04-0.90; p=0.0362) were independent negative predictors of MACE. The optimal value of adiponectin for predicting MACE was 4.23 microg/ml. CONCLUSION. In male patients with myocardial infarction undergoing primary percutaneous coronary intervention, a baseline blood adiponectin but not resistin or leptin is independently predictive of MACE. The other prognostic factors are diabetes mellitus and left ventricular ejection fraction. Topics: Adiponectin; Adipose Tissue; Angioplasty, Balloon, Coronary; Humans; Leptin; Male; Middle Aged; Myocardial Infarction; Predictive Value of Tests; Prognosis; Resistin | 2008 |
Low carbohydrate diet decreases myocardial insulin signaling and increases susceptibility to myocardial ischemia.
Low Carbohydrate Diets (LCD) are a popular intervention for weight loss, but the effect of such diets on myocardial ischemia is not known. Myocardial energy substrates and insulin signaling pathways may be affected by these diets, and both may play a role in protection of ischemic myocardium. We investigated whether LCD increases susceptibility to cardiac injury during ischemia and reperfusion in the isolated rat heart.. Rats were fed LCD (60% kcal from fat/30% protein/10% carbohydrate) or a control diet (CONT; 16%/19%/65%) for 2 weeks. Hearts from rats fed with LCD or CONT were isolated and subjected to normal perfusion in Langendorff mode, with 30 min global low flow ischemia (LFI; 0.3 ml/min) followed by 60 min reperfusion, or 60 min LFI followed by 120 min reperfusion.. LCD diet led to an increase in 3-hydroxybutyrate and lower circulating insulin. LCD diet also resulted in impaired left ventricular performance during LFI, reduced recovery of function following LFI and reperfusion, and 10- to 20-fold increased injury as measured by lactate dehydrogenase release and histologic infarct area. LCD diet also led to lower myocardial glycogen stores and glycogen utilization during LFI, and lower insulin signaling as assessed by Akt phosphorylation at the end of LFI and reperfusion, but no differences in ERK 1/2 phosphorylation.. These results demonstrate that LCD affects myocardial energy substrates, affects insulin signaling, and increases myocardial injury following ischemia-reperfusion in the isolated heart. Topics: Animals; Diet, Carbohydrate-Restricted; Energy Metabolism; Heart Function Tests; Insulin; Leptin; Male; Myocardial Infarction; Myocardial Ischemia; Myocardial Reperfusion; Myocardial Reperfusion Injury; Myocardium; Rats; Rats, Sprague-Dawley | 2008 |
Leptin: a predictor of abnormal glucose tolerance and prognosis in patients with myocardial infarction and without previously known Type 2 diabetes.
High levels of leptin and low adiponectin are associated with Type 2 diabetes mellitus (T2DM) and cardiovascular (CV) disease. We studied the prognostic implications of leptin and adiponectin in patients with acute myocardial infarction (AMI) without previously known Type 2 DM.. One hundred and eighty-one patients were included. Based on an oral glucose tolerance test at hospital discharge (day 4-5), 168 (67% men) had normal or abnormal glucose tolerance (AGT), defined as impaired glucose tolerance or T2DM. Sex- and age-matched healthy persons served as control subjects (n = 185). The associations between fasting serum leptin and adiponectin (day 2) and newly discovered AGT and CV events (CV mortality, non-fatal stroke, reinfarction or severe heart failure) during a median follow-up of 34 months were investigated.. Compared with control subjects, patients of both genders had significantly higher levels of leptin 2 days after an AMI. These levels were higher than those obtained at hospital discharge and 3 months later. Circulating levels of (ln) leptin 2 days after the AMI predicted AGT at discharge (odds ratio 2.03, P = 0.042). Ln leptin at day 2 was the only biochemical variable that significantly predicted CV events both on univariate [hazard ratio (HR) 1.60, P = 0.018] and on multivariate analysis (HR 1.75, P = 0.045). Adiponectin levels did not differ between patients and control subjects and did not relate to AGT or CV events.. Elevated circulating levels of leptin on the first morning after an AMI are associated with the presence of AGT at discharge and with a poorer long-term prognosis. Topics: Adiponectin; Aged; Blood Glucose; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Glucose Intolerance; Glucose Tolerance Test; Humans; Leptin; Male; Middle Aged; Myocardial Infarction; Predictive Value of Tests; Prognosis; Reference Values; Risk Factors | 2008 |
Leptin signalling reduces the severity of cardiac dysfunction and remodelling after chronic ischaemic injury.
Leptin is elevated under conditions of both obesity and heart failure (HF), and activation of leptin receptor (ObR) signalling is known to increase in vivo cardiac contractility and to have anti-hypertrophic effects on the left ventricle (LV). However, it is unknown whether ObR signalling is altered in cardiomyocytes after myocardial infarction (MI) leading to HF, or if a deficiency in ObR signalling leads to worse HF.. In separate experimental protocols, C57BL/6J and leptin-deficient (ob/ob) mice underwent open-chest surgery to induce permanent left coronary artery ligation (CAL) or had a sham operation. Subgroups of ob/ob mice examined were lean (food-restricted), obese (food-ad libitum), and leptin repleted. Four weeks post-surgery, cardiac structure and function was examined by echocardiography, and the activation of cardiac leptin signalling was characterized through quantitative PCR, western blotting, and DNA-binding activities. CAL produced echocardiographic evidence of HF in C57BL/6J mice, elevated circulating leptin, increased cardiomyocyte leptin and ObR expression, and activated myocardial signal transducer and activator of transcription-3 (STAT3). In leptin-deficient ob/ob mice, whether lean or obese, CAL caused increased hypertrophy and dilation, decreased contractility of the LV, and worsened survival relative to wildtype or leptin-repleted mice after CAL. In ob/ob mice, activation of cardiac STAT3 signalling after CAL is enhanced in the presence of leptin and parallels the induction of the STAT3-responsive genes, tissue-inhibitor of metalloproteinase-1 and heat shock protein-70.. These data demonstrate that HF increases ObR signalling in cardiomyocytes and that activation of ObR signalling improves functional outcomes in chronic ischaemic injury leading to HF. Topics: Animals; Cardiomegaly; Heart; Heart Failure; Leptin; Male; Mice; Mice, Inbred C57BL; Myocardial Infarction; Receptors, Leptin; Signal Transduction; STAT3 Transcription Factor; Ventricular Function, Left | 2008 |
Cardioprotective effect of salvianolic acid B on large myocardial infarction mediated by reversing upregulation of leptin, endothelin pathways, and abnormal expression of SERCA2a, phospholamban in rats.
To study the cardioprotective effect of salvianolic acid B (Sal B) on cardiac dysfunction. We hypothesized that hyperleptinemia may correlate with abnormal expression of sarco/endoplasmic reticulum ATPase 2a (SERCA2a), phospholamban (PLB) and endothelin-reactive oxygen species (ET-ROS) pathways in rats with large myocardial infarction (MI).. Large MI was produced by coronary artery ligation for 4 weeks in rats. The rats were divided into four groups: sham, MI, MI+l-Sal B (50 mg/(kg d)), p.o. for 4 weeks), and MI+h-Sal B (100 mg/(kg d)), p.o. for 4 weeks).. In MI rats, hemodynamic and echocardiographic abnormalities, cardiac remodeling, and histological changes with features of cardiac failure were associated with hyperleptinemia accompanied by oxidative stress and upregulated OB-Rb, ET pathway mRNA expression and downregulated SERCA2a and PLB mRNA and protein expressions in the myocardium.. The studies demonstrated that an activated leptin pathway correlated with abnormal expression of SERCA2a, PLB and an activated ET-ROS system in the affected myocardium. Sal B exerts beneficial actions on cardiac function in rats with large MI, mainly suppressing upregulation of leptin and ET pathways and oxidative stress, and recovering the normal expressions of SERCA2a and PLB in myocardium. Topics: Animals; Benzofurans; Calcium-Binding Proteins; Cardiotonic Agents; Disease Models, Animal; Dose-Response Relationship, Drug; Endothelins; Gene Expression Regulation; Leptin; Male; Myocardial Infarction; Oxidative Stress; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Sarcoplasmic Reticulum Calcium-Transporting ATPases | 2008 |
A neutralizing leptin receptor antibody mitigates hypertrophy and hemodynamic dysfunction in the postinfarcted rat heart.
The 16 kDa adipokine leptin has been shown to exert direct hypertrophic effects on cultured cardiomyocytes although its role as an endogenous contributor to postinfarction remodeling and heart failure has not been determined. We therefore investigated the effect of leptin receptor blockade in vivo on hemodynamic function and cardiac hypertrophy following coronary artery ligation (CAL). Cardiac function and biochemical parameters were measured in rats subjected to 7 or 28 days of left main CAL in the presence and absence of a leptin receptor antibody. Animals subjected to an identical treatment in which the artery was not tied served as sham-operated controls. CAL produced myocardial hypertrophy, which was most pronounced 28 days postinfarction as demonstrated by increases in both left ventricular weight-to-body weight ratio and atrial natriuretic peptide gene expression, both of which were abrogated by leptin receptor antagonism. Leptin receptor blockade also significantly improved left ventricular systolic function, attenuated the increased left ventricular end-diastolic pressure, and reduced the expression of genes associated with extracellular matrix remodeling 28 days following CAL. In conclusion, the ability of a leptin receptor-neutralizing antibody to improve cardiac function offers evidence that endogenous leptin contributes to cardiac hypertrophy following CAL. The possibility exists that targeting the myocardial leptin receptor represents a viable and novel approach toward attenuating postinfarction remodeling. Topics: Animals; Antibodies; Disease Models, Animal; Extracellular Matrix; Hemodynamics; Hypertrophy, Left Ventricular; Leptin; Male; Myocardial Infarction; Myocardium; Rats; Rats, Sprague-Dawley; Receptors, Leptin; Time Factors; Ventricular Dysfunction, Left; Ventricular Pressure; Ventricular Remodeling | 2008 |
Relation of increased leptin concentrations to history of myocardial infarction and stroke in the United States population.
Leptin, an adipose tissue-derived hormone, has been linked to cardiovascular outcomes; however, data are limited in the United States population, especially women. To assess the association between leptin concentrations and history of myocardial infarction (MI) and stroke independently of traditional cardiovascular risk factors, we analyzed data from 6,239 subjects (mean age 47 years; 3,336 women) with measurements of serum leptin and full assessment of cardiovascular risk factors from the National Health and Nutrition Examination Survey (NHANES) III. Logistic regression was used to estimate the cross-sectional association of leptin concentrations (highest quartile versus lowest quartile) and history of MI, stroke, and the composite end point of MI or stroke (MI/stroke). Gender-specific models of leptin were adjusted for age, race, dyslipidemia, hypertension, diabetes, smoking, and obesity status. There were 212 men with MI/stroke (5.4%), 154 with MI (4.1%), and 82 with stroke (1.7%). There were 135 women with MI/stroke (2.6%), 74 with MI (1.5%), and 78 with stroke (1.4%). In multivariate analysis, high leptin level was significantly and independently associated with MI/stroke in men (odds ratio [OR] 2.41, 95% confidence interval [CI] 1.20 to 4.93) and women (OR 4.26, 95% CI 1.75 to 10.73); with MI in men (OR 3.16, 95% CI 1.40 to 7.37) and women (OR 3.96, 95% CI 1.29 to 12.72), and with stroke in women (OR 3.20, 95% CI 1.04 to 10.54) but not in men (OR 1.37, 95% CI 0.38 to 3.88). In conclusion, in the United States population, increased leptin concentrations are significantly associated with MI/stroke in men and women independently of traditional cardiovascular risk factors and obesity status. Topics: Adult; Aged; Aged, 80 and over; Female; Humans; Leptin; Male; Middle Aged; Models, Theoretical; Multivariate Analysis; Myocardial Infarction; Risk Factors; Stroke; United States | 2007 |
Size of myocardial infarction induced by ischaemia/reperfusion is unaltered in rats with metabolic syndrome.
Obesity is associated with metabolic syndrome and increased incidence of and mortality from myocardial infarction. The aim of the present study was to develop an animal model with metabolic syndrome and examine how that influences size of myocardial infarcts induced by occlusion and reperfusion of the left anterior descending coronary artery. Sprague-Dawley rats (n = 105) were fed either LF (low-fat) or MHF (moderately high-fat) diets for 13 weeks before coronary occlusion for 45 min, followed by reperfusion for 60 min. Compared with LF-fed and lean MHF-fed rats, obese MHF-fed rats developed metabolic disturbances similar to those seen in the metabolic syndrome, including being overweight by 24% (compared with lean MHF-fed rats), having 74% more visceral fat (compared with LF-fed rats), 15% higher blood pressure (compared with LF-fed rats), 116% higher plasma insulin (compared with lean MHF-fed rats), 10% higher fasting plasma glucose (compared with LF-fed rats), 35% higher non-fasting plasma glucose (compared with lean MHF-fed rats), 36% higher plasma leptin (compared with lean MHF-fed rats) and a tendency to lower plasma adiponectin and higher plasma non-esterified fatty acids. Infarct size was similar in the three groups of rats (36+/-14, 42+/-18 and 41+/-14% in obese MHF-fed, lean MHF-fed and LF-fed rats respectively). In conclusion, rats fed a MHF diet developed metabolic syndrome, but this did not influence myocardial infarct size. Topics: Adiponectin; Animals; Blood Glucose; Cholesterol; Fatty Acids, Nonesterified; Insulin; Leptin; Male; Metabolic Syndrome; Models, Animal; Myocardial Infarction; Myocardial Reperfusion Injury; Myocardium; Rats; Rats, Sprague-Dawley | 2006 |
Obesity--a risk factor or a RISK factor for myocardial infarction?
The detrimental actions of leptin on cardiovascular function are well established. Smith et al. report the novel finding of a reduction of infarct size by exogenous leptin when given at reperfusion. The involvement of the reperfusion injury salvage kinase (RISK) pathway in such reduction of infarct size and its relation to ischemic pre- and postconditioning are discussed and some methodological issues in its assessment are raised. Obesity has possibly opposite effects on the incidence and outcome of myocardial infarction. Topics: Animals; Humans; Leptin; Mice; Myocardial Infarction; Myocardial Reperfusion Injury; Obesity; Protein Kinases; Risk Factors | 2006 |
Increased prolactin in acute coronary syndromes as putative Co-activator of ADP-stimulated P-selectin expression.
Prolactin and leptin are newly recognized platelet co-stimulators due to enhancement of ADP-induced platelet aggregation. The aim of our study was to assess whether both hormones prolactin and leptin play a role as co-activators of platelet activation in patients with acute coronary syndromes. Twenty-one patients with acute coronary syndromes, 10 with stable angina pectoris and 10 controls were studied. Patients with acute coronary syndromes showed significantly higher prolactin and leptin values and a significant increased P-selectin expression on platelets compared to patients with stable angina pectoris or controls. However, patients with acute myocardial infarction as a subgroup of acute coronary syndromes showed the highest prolactin levels as well as ADP stimulated P-selectin expression. In the myocardial infarction subgroup prolactin values showed a significant correlation to ADP stimulated P-selectin expression on platelets (r (2)=0.41; p=0.025), whereas leptin was not correlated. Our data indicate an association between increased prolactin values and enhanced P-selectin expression on platelets in patients with acute coronary syndromes. Therefore, the stress hormone prolactin could be a co-stimulator of platelet activation in these patients. In contrast, the putative platelet activator leptin does not seem to play a major role in acute coronary syndromes. Topics: Adenosine Diphosphate; Aged; Angina, Unstable; Blood Platelets; Coronary Disease; Female; Flow Cytometry; Humans; Leptin; Male; Myocardial Infarction; P-Selectin; Prolactin | 2006 |
[Correlation analysis of increase in serum level of leptin with that of C reactive protein, troponin T and endothelin in patients with acute myocardial infarction].
To determine serum leptin levels in patients with acute myocardial infarction (AMI) and coronary atherosclerosis (CS), and to analyze its correlation with C reactive protein (CRP), troponin T (TnT) and endothelin (ET).. Serum samples from confirmed AMI and CS patients were collected. Leptin and ET were assayed with high sensitive radioimmunoassay, TnT was determined with automatic biochemical analyser, and CRP was determined with enzyme-linked immunosorbant assay (ELISA).. Compared with normal control group, serum leptin, TnT, CRP and ET levels increased significantly (all P<0.01) in AMI patients. Serum levels of other cytokines, except TnT in CS patients, increased significantly compared with normal control group (all P<0.01). Correlation analysis showed that all the changes were not correlated with each other, each being an independent factor. Only serum TnT levels of AMI and CS patients showed a significant difference (P<0.01).. Serum leptin levels of both AMI and CS patients increase significantly without a significant difference between each other, and there is no correlation for leptin with CRP, TnT and ET. Topics: C-Reactive Protein; Coronary Artery Disease; Endothelins; Humans; Leptin; Myocardial Infarction; Troponin T | 2005 |
A case-control pilot study on n-3 polyunsaturated fatty acid as a negative risk factor for myocardial infarction.
The relation between n-3 polyunsaturated fatty acid (PUFA) and nonfatal myocardial infarction is still controversial. A multicenter case-control pilot study on n-3 PUFA as a negative risk factor for myocardial infarction was performed in Niigata prefecture. Seventy-three patients with acute myocardial infarction (AMI) and age and gender matched controls (n = 84) were recruited. Serum leptin levels were significantly higher in patients with AMI than the controls (8.1 +/- 6.7 ng/mL versus 5.8 +/- 3.7 ng/mL, P < 0.01), and serum high-density lipoprotein cholesterol (HDLc) levels were significantly lower in patients with AMI than the controls (46 +/- 10.5 mg/dL versus 60 +/- 15 mg/dL, P < 0.00001). Statistically significant differences were preserved in leptin and HDLc when the data were analyzed separately by gender. Serum levels (%weight) of linolenic acid (C18:3:n3), eicosapentaenoic acid (C20:5:n3), docosapentaenoic acid (C22:5:n3), and total n-3 PUFA were significantly lower in patients with AMI than the control group (P < 0.000001, < 0.05, < 0.05, < 0.05, respectively). The serum n-3 PUFA/saturated fatty acid (SF) ratio and n-3 PUFA/n-9 monounsaturated fatty acid (MUFA) ratio were significantly lower in patients with AMI than the controls (P < 0.05 and < 0.01, respectively). When the subjects were separated into two categories according to an n-3/n-6 PUFA ratio below 0.3 or above 0.3, patients with AMI were more frequently in the former while the controls were more frequently in the latter (P < 0.05). N-3 PUFA may be a negative risk factor for AMI. The results suggest leptin is a risk factor for AMI irrespective of ethnicity and gender. Topics: Aged; Case-Control Studies; Cholesterol; Cholesterol, HDL; Docosahexaenoic Acids; Eicosapentaenoic Acid; Fatty Acids, Omega-3; Female; Humans; Insulin Resistance; Leptin; Male; Middle Aged; Myocardial Infarction; Pilot Projects; Risk Factors | 2005 |
Interactions between fibrinolysis, lipoproteins and leptin related to a first myocardial infarction.
The summarized importance of haemostatic and metabolic variables (insulin, lipids including lipoprotein (a) [Lp(a)] and leptin) in predicting first myocardial infarction, as well as possible interactions among these variables, have not been reported.. A prospective case-control study nested within the Northern Sweden Health and Disease Cohort.. Sixty-two men diagnosed with a first myocardial infarction were sex- and age-matched with 124 controls. Conditional logistic regression was conducted including established risk factors, plasma levels of plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (tPA) mass concentration, von Willebrand factor, insulin, proinsulin, specific insulin, apolipoprotein A-I (apo A-I), Lp(a), and leptin. Interaction analysis was also performed for tPA, apo A-I, Lp(a), leptin and proinsulin.. Smoking, low plasma levels of apo A-I and high plasma levels of cholesterol, Lp(a), tPA, PAI-1, proinsulin and leptin were associated with myocardial infarction in univariate conditional logistic regression analysis. High tPA [odds ratio (OR), 21.3; 95% confidence interval (CI), 2.04-222] and Lp(a) (OR, 7.21; 95% CI, 1.31-39.8) and low apo A-I (OR, 0.15; 95% CI, 0.02-0.93) remained significant risk determinants in multivariate analysis with smoking habits, body mass index, hypertension, cholesterol, and diabetes included as covariates. There were non-significant synergic interactions between high Lp(a) and leptin and tPA, respectively, and between high Lp(a) and low apo A-I.. Plasma levels of tPA, Lp(a), and apo A-I are independently associated with subsequent development of a first myocardial infarction in men. Topics: Apolipoproteins B; Biomarkers; Blood Pressure; Body Mass Index; Case-Control Studies; Diastole; Female; Fibrinolysis; Humans; Leptin; Lipoprotein(a); Lipoproteins; Male; Middle Aged; Multivariate Analysis; Myocardial Infarction; Plasminogen Activator Inhibitor 1; Prospective Studies; Statistics as Topic; Sweden; Systole; Tissue Plasminogen Activator; von Willebrand Factor | 2004 |
Leptin, but not adiponectin, predicts stroke in males.
To test whether leptin and adiponectin are risk markers for a first-ever stroke. RESEARCH DESIGN, METHODS AND SUBJECTS: A nested case-referent study identified 276 cases with first-ever stroke (234 cases with ischaemic and 42 with haemorrhagic stroke). Prior to the stroke, they had participated in population-based health surveys in northern Sweden (median time between survey and stroke was 4.9 years). Referents were matched for sex, age, date and type of health survey, and geographical region. Putative risk markers for first-ever stroke, including blood pressure (BP), diabetes, smoking, body mass index (BMI), cholesterol, leptin, and adiponectin, were analysed by conditional logistic regression analysis.. Increased BMI, high cholesterol and fasting glucose levels, diabetes mellitus and hypertension were found in future stroke patients. Whereas leptin levels were higher in male subjects (P = 0.004), adiponectin did not differ between groups. A high leptin level independently predicted stroke in men (OR = 2.46; 95% CI 1.08-5.62) but not in women. Adiponectin levels did not predict stroke. Males with high leptin levels developed stroke faster than males with low leptin levels (P = 0.0009), independently of traditional risk factors.. Leptin may be an important link to the development of cerebrovascular disease in men, whereas adiponectin does not associate with future stroke. Topics: Adiponectin; Adult; Aged; Biomarkers; Blood Glucose; Body Mass Index; Cholesterol; Diabetes Complications; Diabetes Mellitus; Epidemiologic Methods; Female; Gender Identity; Health Surveys; Humans; Hypertension; Intercellular Signaling Peptides and Proteins; Leptin; Male; Middle Aged; Myocardial Infarction; Proteins; Stroke | 2004 |
Serum leptin and myocardial infarction in hypertension.
The adipose tissue-derived hormone leptin is among the physiologic processes involved in cardiovascular regulation. The aim of the present study was to elucidate if serum leptin may predict cardiovascular risk, particularly myocardial infarction (MI), in hypertensive men and women. In a prospective study cohort of hypertensive men and women, serum leptin was compared in 171 patients with MI and in 342 matched controls. The mean serum concentration of leptin was 25.1 +/- 20.0 ng/ml in the MI patients and 20.0 +/- 16.6 ng/ml in the controls (p = 0.007). The association between serum leptin and MI was independent of traditional risk factors. Leptin concentrations were higher in women than in men. In women, serum leptin was the most important predictor of MI. The present study indicates that serum leptin is associated with MI in a hypertensive population. Leptin concentrations may be of practical importance when estimating the risk of MI, especially in women, where leptin was found to be the most important predictor for MI. Topics: Case-Control Studies; Cohort Studies; Female; Humans; Hypertension; Leptin; Male; Middle Aged; Myocardial Infarction; Prospective Studies; Risk Factors | 2004 |
Role of LDL receptor-related protein (LRP) in coronary atherosclerosis.
The development and progression of coronary atherosclerosis is influenced by a variety of genetic and environmental factors. Among the genetic factors, the cell surface receptor LRP/A2MR (LDL receptor-related protein/alpha2-macroglobulin receptor) was shown to be involved in a variety of biological processes leading to atherosclerotic plaque formation. That is why the individual expression of this receptor may, therefore, be considered as an evident predictor for coronary atherosclerosis. In this clinical ex vivo study the expression was measured by competitive RT-PCR and macroarray analysis in native monocytes. Both methods were first tested in an in vitro model using different human cells and cell lines (fibroblasts: chorion, skin; endothelial cells from umbilical cord vein; monocyte cell line: Mono-Mac-6): after stimulation with an LRP/A2MR ligand, leptin, the anticipated direct effect of this ligand, namely an increase in both receptor mRNA and protein expression, was confirmed. In disease-related ex vivo studies the mRNA and protein-expression of LRP/A2MR was investigated in 36 male patients suffering from myocardial infarction. In comparison to the control group (36 healthy male blood donors), a significant up-regulation of mRNA was detected in the myocardial infarction patient group (control: 122.3 ag/cell versus patients: 223 ag/cell; P<0.001). Investigating the LRP/A2MR protein expression a significant down-regulation of protein expression was determined in the patient group (control: 6 pg/cell versus patients: 1.6 pg/cell; P<0.001). The ratio of LRP/A2MR mRNA and protein expression is obviously an evident marker for coronary atherosclerosis, recommendable for the assessment of the individual coronary risk profile. Topics: Blood Donors; Case-Control Studies; Cell Line; Cells, Cultured; Coronary Artery Disease; Humans; Leptin; Low Density Lipoprotein Receptor-Related Protein-1; Male; Middle Aged; Myocardial Infarction; Receptors, LDL; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger | 2003 |
Serum leptin levels increase following acute myocardial infarction.
Leptin is secreted into the circulation and communicates the peripheral nutritional status to specific hypothalamic centers. Recent studies suggest that leptin may be involved in the acute response to stress, and that its interaction with the hypothalamo-pituitary-adrenal axis and the inflammatory cytokine system may be of clinical importance. Since these systems are activated during acute myocardial infarction (AMI), we studied leptin and cortisol levels during hospitalization in 30 consecutive patients admitted for AMI. The results show that leptin reached its peak on the second day of hospitalization, with a 2-fold increase from its baseline level on admission (p < 0.02). On day 3, leptin levels declined, and were 46%, 9%, and 6% above baseline on days 3, 4 and 5, respectively. The mean cortisol level was elevated on day 1 and decreased toward normal levels thereafter (p < 0.001). The cortisol level did not correlate with leptin concentration throughout the study. These findings suggest that leptin may have a role in the metabolic changes taking place during the first days after an AMI. Topics: Aged; Analysis of Variance; Female; Humans; Hydrocortisone; Leptin; Male; Middle Aged; Myocardial Infarction | 2001 |
Leptin is associated with increased risk of myocardial infarction.
Leptin is involved in the regulation of bodyweight and metabolism in man and might also be involved in the pathophysiology of the insulin resistance syndrome, which is associated with the development of cardiovascular diseases. We tested whether leptin is a risk factor for acute myocardial infarction (AMI) in a nested case-referent study.. Sixty-two men with first-ever AMI were identified who, prior to AMI, had participated in population-based health surveys in Northern Sweden. Referents were matched for sex, age, date and type of health survey, and geographical region. Blood pressure, body mass index (BMI) and the presence of smoking, diabetes and hypertension were recorded. Total cholesterol, apolipoprotein A-1 (apo A-1), apolipoprotein B (apo B), plasminogen activator inhibitor (PAI-1), insulin, and leptin were analysed in stored samples. Their influences on first-ever AMI were analysed by conditional logistic regression analysis.. Men with first-ever AMI had higher BMI, plasma insulin and leptin, and diastolic blood pressure than the referents. Furthermore, they had lower plasma apo A-1 and were more often smokers. Smoking, high leptin, PAI-1 and cholesterol, and low apo A-1 levels were significant risk factors for first-ever AMI in univariate analysis. High leptin (OR 8.97; 95% CI: 1.73-46.5) and cholesterol (OR 5.18; 95% CI: 1.34-20.0) levels remained significant risk factors for AMI in a multivariate model. High apo A-1 was protective (OR = 0.13; 95% CI: 0.03-0.55). The combination of high leptin and low apo A-1 was associated with a particularly pronounced increased risk for AMI.. Plasma leptin strongly predicts first-ever AMI. Our data support the hypothesis that leptin is an important link in the development of cardiovascular disease in obesity. Topics: Adult; Aged; Biomarkers; Case-Control Studies; Humans; Leptin; Logistic Models; Male; Middle Aged; Myocardial Infarction; Risk Factors; Sweden | 1999 |
[Leptinemia in persons with acute myocardial infarct].
The purpose of the study was to verify whether the currently reported relationship between leptinemia and adipose tissue mass can be applied to cases of acute coronary attack. An increased number of cytokines has been reported in severe acute myocardial infarctions so that correlation between cytokines and leptin was investigated. Correlation between standard coronary markers and leptinemia was also studied. We examined 48 probands, patients of the Coronary Unit, Hospital, Sternberk, who were hospitalized for acute myocardial infarction (AMI--16 probands) or for unstable angina pectoris (UAP--22 probands). The persons with AMI had leptinemia and a higher concentration of interleukine-6 (Il-6) and of cardial troponine-I (cTn-I) than individuals without coronary accident (UAP). Early after the acute coronary lesion, leptinemia in persons with AMI displayed a statistically significant positive correlation with concentration of interleukine-6 and subsequently of markers of coronary lesion severity (cTnI). No correlation between leptinemia and body weight was found in those probands. This study proved that leptinemia in the AMI individuals is influenced directly by concentration of cytokines which leads to leptin superproduction by fat cells and leptin resistance. Topics: Adipose Tissue; Adult; Aged; Aged, 80 and over; Angina, Unstable; Female; Humans; Interleukin-6; Leptin; Male; Middle Aged; Myocardial Infarction; Proteins; Troponin I | 1998 |